Q&A - PSLE Math

[Shimmer]

John had $180 more than Ail at first. Both bought a different printer with some money. In the end, Ail was left with $20 more than John. If John’s printer cost 50% more than Ali’s printer,how much does John printer cost?

[MathIzzzFun]

Shimmer:

John had $180 more than Ail at first. Both bought a different printer with some money. In the end, Ail was left with $20 more than John. If John's printer cost 50% more than Ali's printer,how much does John printer cost?

Hi

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cheers.

[MathIzzzFun]

Shimmer:

In the 6A and B,the total number of girls was 100% more than boys. The ratio of boy to girl in 6A is 3:4 and the ratio of boy to girl in 6B is 1:6. If there were 8 more girls in 6a than 6b, find the no. of pupils in 6a.

Hi

6A, Boys: Girls = 3:4 --> 9:12
6B, Boys: Girls = 1:6 --> 2:12

There were 8 more girls in 6A than 6B,
6A, Boys: Girls --> 9u + 6 : 12u + 8 -- total --> 21u + 14
6B, Boys: Girls --> 2u : 12u

Total number of girls was 100% more than boys,
24u + 8 = 2 x (11u +6)
1u --> 2

Total number of pupils in 6A --> 21 x 2 + 14 = 56

cheers.

[MathIzzzFun]

Shimmer:

1)At 9a.m, John was cycling from A to B . At the same time, Mary was cycling from Point B to A using the same route as John. Cycling at a speed of 4km/h faster than Mary, John would pass Mary 300 m away from midpoint.

A)What time did that pass each other?
B) If John took another 3 min to reach B, what time would Mary reach B?

Hi

I think similar questions were discussed before.

When John pass Mary, the meeting point X will be nearer to B, and John would have cycled 300m x 2 = 600m more than Mary.
Time taken to pass each other = 600m/(4km/h) = 9 min
They passed each other at 9.09am

John took 3min to cycle the distance BX, Mary took 9 min to cycle the same distance BX.
For distance AX, Mary will take 9/3 x 9 = 27 min
9.09am + 27min --> 9.36am
Mary reached A at 9.36am

cheers.

[Neat]

Hi!


Faye baked some muffins to sell.
2/3 of them were chocolate muffins and the remaining were walnut muffins.
After she had sold 5/6 of the chocolate muffins and 400 walnut muffins, she had 1/6 of the muffins left.

a) How many muffins did she sell altogether?
b) What percentage of the muffins sold were walnut muffins?

Thanks

[MathIzzzFun]

Neat:

Hi!


Faye baked some muffins to sell.
2/3 of them were chocolate muffins and the remaining were walnut muffins.
After she had sold 5/6 of the chocolate muffins and 400 walnut muffins, she had 1/6 of the muffins left.

a) How many muffins did she sell altogether?
b) What percentage of the muffins sold were walnut muffins?

Thanks

Hi

CM : WM = 2:1 --> 12u : 6u (total 18u)
Sold, CM --> 10u, WM --> 400, total sold --> 5/6 of total = 5/6 x 18u = 15u
10u + 400 = 15u, 1u --> 80
..can you continue from here ?

cheers.

[Neat]

MathIzzzFun:

Neat:

Hi!


Faye baked some muffins to sell.
2/3 of them were chocolate muffins and the remaining were walnut muffins.
After she had sold 5/6 of the chocolate muffins and 400 walnut muffins, she had 1/6 of the muffins left.

a) How many muffins did she sell altogether?
b) What percentage of the muffins sold were walnut muffins?

Thanks

Hi

CM : WM = 2:1 --> 12u : 6u (total 18u)
Sold, CM --> 10u, WM --> 400, total sold --> 5/6 of total = 5/6 x 18u = 15u
10u + 400 = 15u, 1u --> 80
..can you continue from here ?

cheers.

[quote]Hi! MathIzzzFun[/quote]Yes, I can.

Thank you so much for your prompt reply.

:thankyou:

[Shimmer]

MathIzzzFun:

Shimmer:

In the 6A and B,the total number of girls was 100% more than boys. The ratio of boy to girl in 6A is 3:4 and the ratio of boy to girl in 6B is 1:6. If there were 8 more girls in 6a than 6b, find the no. of pupils in 6a.

Hi

6A, Boys: Girls = 3:4 --> 9:12
6B, Boys: Girls = 1:6 --> 2:12

There were 8 more girls in 6A than 6B,
6A, Boys: Girls --> 9u + 6 : 12u + 8 -- total --> 21u + 14
6B, Boys: Girls --> 2u : 12u

Total number of girls was 100% more than boys,
24u + 8 = 2 x (11u +6)
1u --> 2

Total number of pupils in 6A --> 21 x 2 + 14 = 56

cheers.

Thanks so much KaisuGrandMaster !

[jonaandr]

Help needed for these 4 questions - many thanks in advance!


1. Roy,Sam and Ted had a sum of money. Roy had 80% of Sam’s money. Sam had 60% of Ted’s. After Roy gave $12 to sam, he had 5/7 of what Sam had. How much more money did Ted have than Sam in the end?

2. Jerry bought four times as many pencils as notebooks and spent a total of $21.60. He spent $2.40 more on the notebooks than the pencils. Given that a notebook costs $3.20 more than a pencil, find the cost of a pencil.

3. Ms Lee baked 24 more chocolate muffins than banan muffins. After she gave away 1/6 of the chocolate muffins and 3/8 of the banana muffins, she was left with 35 more chocolate muffins than banana muffins. How many chocolate muffins did she bake at first?

4. At first, ravi had $200 more than vincent. He gave 40% of his money to Vincent. vincent then gave 25% of his money to ravi. In the end, Vincent had $68 more than Ravi. How much did Vincent give Ravi?

[tianzhu]

jonaandr:

4. At first, ravi had $200 more than vincent. He gave 40% of his money to Vincent. vincent then gave 25% of his money to ravi. In the end, Vincent had $68 more than Ravi. How much did Vincent give Ravi?

Hi

You may draw MD to show the transactions or choose to work using units.

At first
Ravi ----- 20 units + 200
Vincent ------20 units

I use 20 units instead of 10 units to avoid working with decimals during future transfer.

Ravi gave 8 units + 80 to Vincent. He was left with 12 units + 120

Vincent now had 28 units + 80

Vincent then gave 25% of his money to Ravi.
25% ------- 7 units + 20

In the end
Ravi --------- 19 units + 140
Vincent ------- 21 units + 60

19 units + 140 + 68 ------ 21 units + 60
1 unit ----- 74

Vincent gave (7*74) + 20 or 538 to Ravi.

Best wishes