Tutor MathsGuru: Ask me for your burning Maths questions!

[MathIzzzFun]

2DMommy:

Dear all


Need help with these two questions :
1) Zach had a total of 2050 black and red marbles. He lost 3/5 of his black marbles and bought another 150 red marbles. As a result, the number of red marbles he had was 1/4 of the remaining black marbles. How many more black marbles than red marbles had he at first?\t

2) Vanessa, Hilton and Dolly were given a box of sweets. Vanessa took 1/3 of the sweets and another 20 from the box. Hilton took 0.5 of the remainder and another 40 from the box. Dolly took the remaining 30 sweets and there were no sweets left in the box.\t\t\t
a) How many sweets were there in the box at first ?\t\t\t
b) How many sweets did Hilton have finally ?\t

Thanks !

Hi

Q1

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Q2 is a typical \"work backwards\" problem sum. For eg. start from the end, we have, 30 (by Dolly)+40 (by Hilton)= 70 =0.5 of \"last\" remainder Hilton took from, so last remainder = 2 x 70= 140 and then work back again to initial state.. give it a try !

cheers.


cheers.

[MathIzzzFun]

Herbie:

thanks mathsizzfun, sorry, i just dscovered i hv a topo error, d should be= 2.5m and not 25m.


Thanks for working it out for me! Many thanks!!

that's alright... u r welcome.

cheers.

[she0407]

thanks MathIzzzFun for your help. :rahrah:

[2DMommy]

Thanks mathsizzfun !

[2DMommy]

Please help me with these 2 questions again. Not too difficult i think but i am stupid lah :oops:


1) The ratio of Ahmad's age to Sun's age is 5 : 3 now. 4 years ago,
the ratio was 7 : 4. How\told is Ahmad now ?\t

2) Aunt Rosie bought an equal number of curry puffs and cupcakes for a tea party. The curry puffs were bought at 7 for $2 and the cupcakes were bought at 5 for $3. She paid $33 more for the cupcakes than for the curry puffs.\t\t\t\t\t\t\t\t
a) How many curry puffs did Aunt Rosie buy ?\t\t\t\t
b) How much did Aunt Rosie pay for the curry puffs ?\t\t\t\t\t\t\t\t\t
Thanks

[MathIzzzFun]

2DMommy:

Please help me with these 2 questions again. Not too difficult i think but i am stupid lah :oops:


1) The ratio of Ahmad's age to Sun's age is 5 : 3 now. 4 years ago,
the ratio was 7 : 4. How\told is Ahmad now ?\t

2) Aunt Rosie bought an equal number of curry puffs and cupcakes for a tea party. The curry puffs were bought at 7 for $2 and the cupcakes were bought at 5 for $3. She paid $33 more for the cupcakes than for the curry puffs.\t\t\t\t\t\t\t\t
a) How many curry puffs did Aunt Rosie buy ?\t\t\t\t
b) How much did Aunt Rosie pay for the curry puffs ?\t\t\t\t\t\t\t\t\t
Thanks

Hi

1) for problem sums on \"age\", the key consideration is the age difference will remain the same.

Age now, Ahmad:Sun = 5:3 = 15u : 9u (diff 6u)
Age 4 years ago, Ahmad:Sun = 7:4 = 14u:8u (diff 6u)
so 15u - 14u = 4, 1u = 4

Ahmad's age now = 15 x 4 = 60 years old.

2) Find cost of equal number of cupcakes & curry puffs
cost of 35 (7 x5 ) curry puffs = 5 x $2 = $10
cost of 35 (5 x7) cupcakes = 7 x $3 = $21

every 35 cupcakes cost $11 more than 35 curry puffs

$33/$11 = 3

so 3 x 35 = 105 cupcakes will cost $33 more than 105 curry puffs.

a) Auntie Rosie bought 105 curry puffs
b) cost of 105 curry puffs = 105/7 x $2 = $30

cheers.

[blitz]

PLs assist.

Belinda has 20% more stickers than Yi Xizng. Yi Xiang has 25% more stickers than Sabrina.
(a)What is the ratio of Belinda’s stickers to Sabrina stickers?
(b)Yi Xiang gave some stickers to Sabrina so tha they each had the same number of stickers. Now Belinda has 36 more stickers than Sabrina. How many stickers does Belinda have?

[blitz]

One more question…thanks in advance


60% of people at a performance were adults. 75% of the children at the performance were girls. There were 36 more girls than boys. Halfway thru the performance, some girls left. After that, 2/9 of the remaining people were girls.

How many girls left the performance?

I got the answer as 34, is that correct?

[MathIzzzFun]

blitz:

PLs assist.

Belinda has 20% more stickers than Yi Xizng. Yi Xiang has 25% more stickers than Sabrina.
(a)What is the ratio of Belinda's stickers to Sabrina stickers?
(b)Yi Xiang gave some stickers to Sabrina so tha they each had the same number of stickers. Now Belinda has 36 more stickers than Sabrina. How many stickers does Belinda have?

Hi

Q1
Belinda : Yi Xiang = 120 : 100 = 6 :5
Yi Xiang : Sabrina = 125 : 100 = 5 : 4
Belinda : Yi Xiang : Sabrina = 6 : 5 : 4

a) Belinda : Sabrina = 6 : 4 = 3 : 2

b) Belinda : Yi Xiang : Sabrina = 6u : 5u : 4u
After Yi Xiang gave some stickers to Sabrina, they each had the same = (5u+4u)/2 = 4.5u

Belinda had 36 more stickers than Sabrina -> 6u - 4.5u = 1.5u = 36
1u = 24
6u = 144

Belinda had 144 stickers.

cheers.

[MathIzzzFun]

blitz:

One more question...thanks in advance


60% of people at a performance were adults. 75% of the children at the performance were girls. There were 36 more girls than boys. Halfway thru the performance, some girls left. After that, 2/9 of the remaining people were girls.

How many girls left the performance?

I got the answer as 34, is that correct?

Hi

I got 18.

From the first part of question, you will get -
Adults : Girls : Boys = 108 : 54 : 18
then 7/9 of remaining people = 108 + 18 = 126, 1/9 = 18, 2/9 = 36 girls remained.

Number of girls who left the performance = 54 - 36 = 18

cheers.