Q&A - PSLE Math

[shruthi]

J takes 6 hours to paint a house.If D helps him,they would take 4 hours.How long will D take to paint the house himself?

[ck123]

Thanks tianzhu

[shruthi]

Tony is 38 years old.Kelly is 22 years old.How many years ago was Kellys age 1/3 of Tonys age?

[shruthi]

J and E each have some marbles.If J gives 36 marbles to E,both of them will have the same number of marbles.If E gives 12 marbles to J,the number of marbles that J has to the number of marbles E has will be in the ratio 5:1.How many marbles does each girl have?

[Mvm]

shruthi:

Tony is 38 years old.Kelly is 22 years old.How many years ago was Kellys age 1/3 of Tonys age?

14 years ago k will be 22-14=8 t was 38-14=24
8 is 1/3 of 24.

And: 14 years ago.

[tianzhu]

Verysuperkiasu:

Thank you so very much!!!

Hi

Good Morning.

You're welcome.

Best wishes

[tianzhu]

ck123:

Thanks tianzhu

Hi

Good Morning.

You're welcome.

Best wishes

[tianzhu]

Verysuperkiasu:

Thank you so much, tianzhu!

Hi

Good Morning.

You're welcome.

Best wishes

[tianzhu]

shruthi:

R and D had $1250 altogether.After R spent 80% and D spent 40%,D had twice as much money left as R.Find the amount of money D had in the end.

Hi

You may use MD.

Start with D in the end.

D
Left ----- 6 units (60%)
Spent ----- 4 units (40%)

R
Left ------ 3 units (20%) ----- D had twice as much money left as R.
Spent ------ 12 units (80%)

25 units ------ 1250
1 unit ------ 50

In the end, D ------ 6 units ------ 6*50 ------ 300

Best wishes

[tianzhu]

shruthi:

J takes 6 hours to paint a house.If D helps him,they would take 4 hours.How long will D take to paint the house himself?

Hi

One way to solve it.

In 1h, J paints 1/6 of a house.

In 1h, J and D paint 1/4 of a house.

1/4 – 1/6 ------ 1/12

In 1h, D paints 1/12 of a house.

Hence, he takes 12h to paint the house himself.

Best wishes