Q&A - PSLE Math

[peggy]

Got it! Thanks Jieheng.

[jieheng]

peggy:

Got it! Thanks Jieheng.

Hi peggy ,

You are welcome .

Regards,

[shurley197323]

Hi, pls help and sorry for asking so often.

(1) Alan had thrice as many oranges as mangoes. After he sold 136 oranges and threw away 12 rotten mangoes, the no of oranges left was the no of mangoes left. How many mangoes did he have left? (ans : 40)

(2) lynn order some balloons for a carnival. 2/7 of the ballon are gold. The rest of the ballons are silver,red and blue in the ratio of 6:3:11. There are 120 fewer gold balloons than blue balloons. How many silver ballon did lynn order?

[shurley197323]

Very sorry, 2 more questions to ask

(1) A salesman received a commission of $3 for every set of books he sold. For every 15 sets of books he sold, he will receive additional $15. How many sets of books did he sell if he receive a total commission of $216. (ans :57)

(2)To buy a story book.Gilbert started saving $0.40 every day.Helena starts saving 5 days after Gibert started and she saves $0.40 more than Gilbert every day.When Gibert saved enough money to buy the storybook.Helena had already saved $14 more than him.How much does Gilbert book cost? (ans:$18)

[CoffeeCat]

shurley197323:

Very sorry, 2 more questions to ask

(1) A salesman received a commission of $3 for every set of books he sold. For every 15 sets of books he sold, he will receive additional $15. How many sets of books did he sell if he receive a total commission of $216. (ans :57)

(2)To buy a story book.Gilbert started saving $0.40 every day.Helena starts saving 5 days after Gibert started and she saves $0.40 more than Gilbert every day.When Gibert saved enough money to buy the storybook.Helena had already saved $14 more than him.How much does Gilbert book cost? (ans:$18)

(1)
For every 15 sets of books he sold, he will receive additional $15.
This suggests we must first find out the total commission for every 15 sets of books. $15*3 + $15 = $60.
$216 / $60 = 3 r $36.
Hence there are 3 groups of 15 sets (45 sets) and $36/ $3 = 12 sets of books (57 in total).

(2)
To make easier comparison on a day-to-day basis (because we know Helena saved up more than Gibert), we must find out how much headstart Gibert has before Helena started saving : $0.40*5 = $2.

Despite having $2 headstart, Helena still end up with $14 more. This suggest after Helena started saving, she saved a total of $16 more than Gibert.
Helena thus saved for a total of $16/$0.40 = 40days.
Gibert saved for a total of 45 days.
Hence cost of book is 45*$0.40 = $18.

[HappyFaye]

shurley197323:

Hi, pls help and sorry for asking so often.

(1) Alan had thrice as many oranges as mangoes. After he sold 136 oranges and threw away 12 rotten mangoes, the no of oranges left was the no of mangoes left. How many mangoes did he have left? (ans : 40)

http://postimage.org/image/1wo2gxf5w/

[HappyFaye]

shurley197323:

(2) lynn order some balloons for a carnival. 2/7 of the ballon are gold. The rest of the ballons are silver,red and blue in the ratio of 6:3:11. There are 120 fewer gold balloons than blue balloons. How many silver ballon did lynn order?

http://postimage.org/image/i3g55738/

[QuiteKSMum]

To : Tianzhu and Dharma,


Just want to say :thankyou: . We learned a lot from you guys during our prep. for last yr's PSLE. Both for Science, and esp Maths. ( only just became a member; hence the belated thanks!)

[MathIzzzFun]

shurley197323:

Hi, pls help and sorry for asking so often.

(1) Alan had thrice as many oranges as mangoes. After he sold 136 oranges and threw away 12 rotten mangoes, the no of oranges left was the no of mangoes left. How many mangoes did he have left? (ans : 40)

Hi

For this question, mangoes left = 50. To get an answer of 40 the question is \"Alan had thrice as many oranges as mangoes. After he sold 136 oranges and threw away 12 rotten mangoes, the no of oranges left was half the no of mangoes left. How many mangoes did he have left?

cheers.

[tianzhu]

QuiteKSMum:

To : Tianzhu and Dharma,


Just want to say :thankyou: . We learned a lot from you guys during our prep. for last yr's PSLE. Both for Science, and esp Maths. ( only just became a member; hence the belated thanks!)

Hi QuiteKSMum

Good Morning.

You're welcome.

Best wishes