Q&A - PSLE Math

[SOS mum]

Ps help the following qns. Many tks and God Bless:)

(2) Jason and Ricky have 276 marbles altogether. 1/4 of Jason's marbles is 15 more than 1/5 of Ricky's marbles.
(a) How many marbles does each boy have?
(b) Find the ratio of the number of Ricky's marbles to the number of Jason's marbles.

If Rick's has 5u, 1/4 of Jason would be u+15. Which makes Jason total to be 4u +60

Total = 276 = 5u +4u +60
276 = 9u + 60
216 = 9u
u = 24

Jason = 5u = 120
Ricky = 4u + 60 = 156

b) R : J => 156 : 120 => 13: 10

Tks Ender for the 2 answers!

[sushi88]

Tks Sushi88
However, when i used the same concept for the following qn, it cldnt solve. Ps help. Tks and God Bless:)

The ratio of the number of muffins to the number of pies in a bakery was 4:1. After another 63 muffins and 46 pies were baked, the ratio became 3:1. How many muffins and pies were there in the bakery at first?

SOS mum, actually the method works for this question too. Concept of ratio to find u. Only difference is previous question wants to find only one item, girls at first so multiply the u for the girls' part only but this question wants to find total items so multiply the u for total parts after u is solved.

Before:
M:P
4u: u
After:
M: P
4u+63: u+46
3 : 1

(4u+63)/ (u+46) = 3/1
4u+63 = 3(u+46)
4u+63 = 3u+138
u = 138-63=75

Hence total muffins and pies at first is 5u = 5 x 75 = 375

[sushi88]

Ps help the following qns. Many tks and God Bless:)

(1) The total number of game cards that Fandi and Geetha had was the same as the number that Eugene had. The total number of game cards that Eugene and Geetha had was 5 times the number that Fandi had.
(a) What was the ratio of the number of game cards that Eugene had to the number of game cards that Geetha had to the number of game cards that Fandi had?
(b) Eugene had 118 game cards more than Fandi. How many game cards did the 3 children have altogether?

Alternative method using diagram.

[tutor76]

Anyone heard of the 3/4 pi d formulae to calculate perimeter of a semicircle ?

[SOS mum]

Ps help the following qns. Many tks and God Bless:)

(1) The total number of game cards that Fandi and Geetha had was the same as the number that Eugene had. The total number of game cards that Eugene and Geetha had was 5 times the number that Fandi had.
(a) What was the ratio of the number of game cards that Eugene had to the number of game cards that Geetha had to the number of game cards that Fandi had?
(b) Eugene had 118 game cards more than Fandi. How many game cards did the 3 children have altogether?

Alternative method using diagram.

Thank u very much, Sushi88

[SOS mum]

Hi, ps help. Many thks and God Bless:)

1) Irene, Doreen, Shawnia and Ruth made some balloons. Doreen made 252 balloons at first. Ruth donated some of her balloons and her number of balloons decreased by 20%. Irene made another 40% of her balloons. Shawnia gave away 30 fewer balloons than what Doreen had made. In the end, they had an equal number of balloons. How many balloons did they make altogether at first?

2) In a bakery shop, there are some curry, sardine and kaya buns. There are 216 more curry than sardine buns. There is 3 times as many curry as kaya buns. There is 12% as many sardine buns as the total number of buns. How many buns are there in the bakery shop?

(3) Mrs Letilia made 45 fewer dumplings than Mrs Hagans. Mrs Hagans decided to give 20% of her dumplings to Mrs Letilia. Mrs Letilia then gave 2/3 of her dumplings to Mrs Hagans. In the end, Mrs Hagans had 69 more dumplings than Mrs Letilia. How many dumplings did Mrs Hagans give to Mrs Letilia?

[SOS mum]

Sorry, some more qns:

At the Woodlands Checkpoint, there were 24 more cars than lorries waiting at the gantry for clearance at first. After 2/3 of the cars and 20% of the lorries had cleared the gantry, there were 20 fewer cars than lorries waiting at the gantry. How many cars had cleared the gantry?

(2) Mrs Sharee bought a total of 38 cups and saucers for her upcoming party. She bought 10 more cups than saucers. The cost of a saucer was 2/9 of the total cost of a cup and a saucer. Given that she paid a total of $215.60 for all the cups and saucers, what was the cost of a cup?

[SOS mum]

Mrs Wong prepared some orange syrup in a large pot. She transferred 60% of the syrup into an empty bottle. 75% of the remaining syrup was poured in to a mug leaving 210 litres of syrup left in the pot. Given that the bottle was 70% full, how much more would Mrs Wong need to prepare to fill up the bottle completely?

2) Yvonne, Maple and Florence were given an equal number of pins to decorate their rooms. Yvonne used 60% of her pins, Florence used 20% more pins than Yvonne and Maple used 48 pins. Given that they had a total of 78 pins left, how many pins were given to each of them at first?

3) There are 15 fewer rings than bracelets in a shop. There is 21 more bracelets than necklaces. There is 23 more hairclips than rings. There is 2/9 as many necklaces as bracelets and hairclips. How many rings are there in the shop?

[origami]

Last year, there were 375 volunteers for a sports event. This year, the number of male volunteers increased by 20% and the number of female volunteers increased by 30%. In the end, there was an equal number of. Male and female volunteers this year. How many female volunteers joined this year?

Thank you very much!!

[Ender]

Mrs Wong prepared some orange syrup in a large pot. She transferred 60% of the syrup into an empty bottle. 75% of the remaining syrup was poured in to a mug leaving 210 litres of syrup left in the pot. Given that the bottle was 70% full, how much more would Mrs Wong need to prepare to fill up the bottle completely?

After she transferred 60% to a bottle, there will be 40% left in the pot.

75% of the remainder 40%, is also 3/4 of the remainder 40%. 3/4 of the 40% remainder went to the mug means 30% went into the mug, and 10% left in the pot.
Therefore 10% => 210 litres.
60%=> 1260 litre, that's to the bottle.

70% of bottle = > 1260 litres,
She needs 30% more to fill up the bottle,
10% => 1260/7 = 180 Litres
30% = > 540 litres#