Tutor MathsGuru: Ask me for your burning Maths questions!

Dharma

Muffins:
Hey Dharma, long time no cybersee! what you been up to nowadays?

Hi Muffins,

Nice to hear from u. I've been a silent observer recently. How have u been buddy?

Muffins

I’ve been awesome, just came back from ACS(I), very exhausted…

Dharma

KSP:
Hi mathsguru,

Have you tried doing the questions posted in \"Are you smarter than a PSLE Kid\" at http://www.blogtv.sg ? (http://blogs.blogtv.sg/starbloggers/2009/10/23/math-quiz/
10 questions, 40 minutes later, the 12-year-old boy emerged triumphant, having answered 4 questions correctly. The 31-year-old banker managed only 1 correct question. So do you think you’re smarter than a 12-year-old? Here are the 10 questions we posed to our two wonderfully brave contestants.)

Here are the questions and answers. It will be very helpful if you can show us the working. Thank you in advance.

QUESTION 1
Bryan invited 20 more boys than girls to a party. 3/4 of the boys and 2/3 of the girls came. 19 people didn’t come. How many people did he invite?

QUESTION 2
Of the visitors in a museum, 40% are children, 3/4 of the adults are women.
a) what is the ratio of children:men:women.
b) the second day, children number increased by 20%, adults number remain the same but women is 3/5 of adult. if there are 336 more children than women, how many visitors on second day

QUESTION 3
The figure below, not drawn to scale is made up of a big circle, two semicircles, two quadrants and two squares.
a) Find the perimeter of the shaded figure
b) find the area of the shaded figure

http://www.postimage.org/image.php?v=aV61DoS

QUESTION 4
A millipede is climbing up a wall. For every 3cm it climbs, it slips by 1cm. It takes 3 seconds to climb 1 cm and 1 second to slip by 1cm.
a) How far would the millipede have climbed after 1 minute?
b) How long would the millipede take to climb 56cm?

QUESTION 5
There are red and green beads in a bag. When 75 green beads are added, the percentage of red beads decreased from 30% to 20%. How many red beads are there in the bag?

QUESTION 6
Kavita had 50% fewer erasers than Mark. After Mark gave 15 of his erasers to Kavita, Kavita had 40% fewer erasers than Mark. How many erasers did Kavita have at first?

QUESTION 7
The ratio of Ryan’s pocket money to John’s pocket money was 3 : 2. After Ryan saved $15 and John spent $8, the ratio of Ryan’s pocket money to John’s pocket money was 3 : 1. How much money did Ryan have at first?

QUESTION 8
Shop A has 156 kg of rice. Shop B has 72 kg of rice. After both shops sold an equal amount of rice, the ratio of rice that shop A has to shop B is 4:1. Find the amount of rice sold by each shop.

QUESTION 9
6/14 of the chairs in a hall are in rows of 13. Half of the chairs are in rows of 7. There are 112 more chairs in rows of 7. The rest of the chairs are stacked up. Find the total number of chairs.

QUESTION 10
Tank A is filled with water to its brim. Water is then poured from Tank A to Tank B until both share the same height. What is this height?

http://www.postimage.org/image.php?v=aV61KTi

Answers.

QUESTION 1
68 people were invited

QUESTION 2
a) 8:3:9
b) 3024 visitors

QUESTION 3
a) 125.6cm
b) 192.5cm squared

QUESTION 4
a) 12cm
b) 4min 36 sec

QUESTION 5
There are 45 red beads in the bag

QUESTION 6
Kavita had 120 erasers at first

QUESTION 7
Ryan had $39 at first

QUESTION 8
Each shop sold 44 kg of rice.

QUESTION 9
There were a total of 1568 chairs.

QUESTION 10
The height of the water is 25 cm.

Hi KSP,

http://www.postimage.org/image.php?v=aVWPEaJ

Dharma

KSP:
Hi mathsguru,

Have you tried doing the questions posted in \"Are you smarter than a PSLE Kid\" at http://www.blogtv.sg ? (http://blogs.blogtv.sg/starbloggers/2009/10/23/math-quiz/
10 questions, 40 minutes later, the 12-year-old boy emerged triumphant, having answered 4 questions correctly. The 31-year-old banker managed only 1 correct question. So do you think you’re smarter than a 12-year-old? Here are the 10 questions we posed to our two wonderfully brave contestants.)

Here are the questions and answers. It will be very helpful if you can show us the working. Thank you in advance.

QUESTION 1
Bryan invited 20 more boys than girls to a party. 3/4 of the boys and 2/3 of the girls came. 19 people didn’t come. How many people did he invite?

QUESTION 2
Of the visitors in a museum, 40% are children, 3/4 of the adults are women.
a) what is the ratio of children:men:women.
b) the second day, children number increased by 20%, adults number remain the same but women is 3/5 of adult. if there are 336 more children than women, how many visitors on second day

QUESTION 3
The figure below, not drawn to scale is made up of a big circle, two semicircles, two quadrants and two squares.
a) Find the perimeter of the shaded figure
b) find the area of the shaded figure

http://www.postimage.org/image.php?v=aV61DoS

QUESTION 4
A millipede is climbing up a wall. For every 3cm it climbs, it slips by 1cm. It takes 3 seconds to climb 1 cm and 1 second to slip by 1cm.
a) How far would the millipede have climbed after 1 minute?
b) How long would the millipede take to climb 56cm?

QUESTION 5
There are red and green beads in a bag. When 75 green beads are added, the percentage of red beads decreased from 30% to 20%. How many red beads are there in the bag?

QUESTION 6
Kavita had 50% fewer erasers than Mark. After Mark gave 15 of his erasers to Kavita, Kavita had 40% fewer erasers than Mark. How many erasers did Kavita have at first?

QUESTION 7
The ratio of Ryan’s pocket money to John’s pocket money was 3 : 2. After Ryan saved $15 and John spent $8, the ratio of Ryan’s pocket money to John’s pocket money was 3 : 1. How much money did Ryan have at first?

QUESTION 8
Shop A has 156 kg of rice. Shop B has 72 kg of rice. After both shops sold an equal amount of rice, the ratio of rice that shop A has to shop B is 4:1. Find the amount of rice sold by each shop.

QUESTION 9
6/14 of the chairs in a hall are in rows of 13. Half of the chairs are in rows of 7. There are 112 more chairs in rows of 7. The rest of the chairs are stacked up. Find the total number of chairs.

QUESTION 10
Tank A is filled with water to its brim. Water is then poured from Tank A to Tank B until both share the same height. What is this height?

http://www.postimage.org/image.php?v=aV61KTi

Answers.

QUESTION 1
68 people were invited

QUESTION 2
a) 8:3:9
b) 3024 visitors

QUESTION 3
a) 125.6cm
b) 192.5cm squared

QUESTION 4
a) 12cm
b) 4min 36 sec

QUESTION 5
There are 45 red beads in the bag

QUESTION 6
Kavita had 120 erasers at first

QUESTION 7
Ryan had $39 at first

QUESTION 8
Each shop sold 44 kg of rice.

QUESTION 9
There were a total of 1568 chairs.

QUESTION 10
The height of the water is 25 cm.

Hi KSP,

This one for Q1

http://www.postimage.org/image.php?v=Pq1a56BS

mathsguru

Hi everyone,

My sincere apologies for not being active the past couple of weeks. Was down with a bad strain of flu towards the end of 2009 and was away on a holiday and now I'm back in action...ha! (but unfortunately, the flu bug decided to pay me a visit yet again...so i started 2010 with a *sneeze* and *cough*...urghhh!!)

Anyway, stayed up the whole night to do up all the outstanding solutions...hopefully, they make sense and can help you all when you explain to your DS/DD...

Will upload them accordingly in the next few posts. If you need clarification, pls feel free to shout! Hehe...

And before I forget, here's wishing everyone in KiasuParents.com a Happy 2010!! May all hard work reap deserving results!!

Cheers,
MathsGuru

mathsguru

KSP:
Hi mathsguru,

Have you tried doing the questions posted in \"Are you smarter than a PSLE Kid\" at http://www.blogtv.sg ? (http://blogs.blogtv.sg/starbloggers/2009/10/23/math-quiz/
10 questions, 40 minutes later, the 12-year-old boy emerged triumphant, having answered 4 questions correctly. The 31-year-old banker managed only 1 correct question. So do you think you’re smarter than a 12-year-old? Here are the 10 questions we posed to our two wonderfully brave contestants.)

Here are the questions and answers. It will be very helpful if you can show us the working. Thank you in advance.

Hi KSP,

Here are my solutions. These are typical primary school questions which are best solved using models/diagrams. I'm not surprised why the banker cannot solve most of them...

mathsguru

RedRedWine:
Hi mathsguru,

here's another question, i can solve using algebra equation but don't know how to explain to my son. Hope you can help.

Feng Rui has 225 more Singapore stamps than Malaysia stamps. After selling 3/5 of the Singapore stamps and 1/3 of the Malaysia stamps, he has 858 stamps left. How many stamps does Feng Rui have at first?

TIA.

Hi RedRedWine,

Here's my solution...hopefully it's clear enough!

http://www.postimage.org/image.php?v=Pq1bDjbA

Cheers,
MathsGuru

mathsguru

Vikaesh:
Dear MathsGuru, i really admire your expertise in Mathematics. Could you be so kind as to share with me some of your Seconday one Express Notes of any subject....(all others could share note if you please)

P.S. : I understand if you do not want to share them with me...

Hi Vikaesh,

I would love to help you, but I do not have my Sec One notes anymore. Really sorry! It's been mannnyyy years since I was a Sec One student... :faint:

Here's wishing you all the best in your Secondary school life and academic pursuit!! Be a consistent worker and build your Maths foundation well. It will serve you well in Upper Sec and JC.

Cheers,
MathsGuru

mathsguru

YLH88:
Hi mathsguru,

Need your help to solve the below 3 questions from P6 :?: . I know the last question has been solved in the forum, but I still don't quite understand.

Thank you so much for your help !!

Hi YLH88,

Here are my solutions. As for the Jim and Ken question, may I ask which part puzzles you?

Perhaps you can share with me, then I can try to explain accordingly.

http://www.postimage.org/image.php?v=Ts1QRdDA

http://www.postimage.org/image.php?v=Ts1QR8Ei

Cheers,
MathsGuru

mathsguru

sachiko:
Hi

I would appreciate if you could help me to solve the following questions:

Thank you

Hi Sachiko,

Here are my solutions.

http://www.postimage.org/image.php?v=Ts1QRA4S

http://www.postimage.org/image.php?v=Ts1QRxAJ

Cheers,
MathsGuru

Tutor MathsGuru: Ask me for your burning Maths questions!

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