Friday, September 30, 2011

Whole Number P6 2011 PSLE P1 Q15

Sally has a book which has 525 pages. From Monday to Thursday she reads 15 pages per day and Friday to Sunday she reads 30 pages per day. What is the least number of days she needs to finish reading the whole book?


Friday to Sunday à 30 x 3 = 90

Monday to Thursday à 15 x 4 = 60

1 set (7 days)  -->  90 + 60 = 150

525  ÷  150  =  3 sets remainder 75 pages

75 ÷ 30  =  2 r 15 days 
{So can start on Thursday, Friday or Saturday}

3  x  7  =  21

21  +  3  =  24  days


It is  24  days.

4 comments:

  1. Question 16:
    Answer:
    Pythagoras theorem: 15 squared + 8 squared= 289
    Square root of 289= 17
    Answer: 17cm

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  2. If u say is 24,when you count one by one it is 26 not 24!

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  3. @Anonymous they said the LEAST number of days.You can start from Friday, and not Monday.

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  4. hi! i agree wiv anonymous. if u calculate, shouldnt it be 75 days= 5 days? so u shld take 21 days + 5 days = 26days. so even if it is least no. of days bud, i tink 24 days cnnt wrk out as i tink 26 days is better? maybe u want to try it again? i might be wrong...

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