
By: foresight (offline) Monday, August 06 2012 @ 04:41 AM CDT (Read 887 times)



foresight 
Please help to solve these sums,thank you.
qn :12
Don had 4 times as much as money as Mei Mei.After he gave $9 to Mei Mei and spent $15 .Don and Mei Mei had the same amount of money.How much money did Don have at first ?
qn 13
The table shows thw number of students from 5 classess attending a camp.
: If all the students are grouped into teams of 5 students each, 1 student is left out.If they are grouped into the teams of 7 students each, 5 students are left out.What is the least number of students from class 5B ?
classess no of students campers
5A 33
5B ?
5C 25
5D 12
5E 7

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Registered: 05/30/10 Posts: 3





By: GIM (offline) Wednesday, August 08 2012 @ 09:37 AM CDT



GIM 
Q12
D 
<(15)>(9)
M(+9)
From the model,
3 units> 9 + 15 + 9 = 33
1 unit > 33 / 3 = 11
Don > 11 x 4 = $44 at first
Q13
Tabulate to find solution
Since the sum of pupils from other classes > 33+25+12+7= 77, we should start with number greater than 77
Multiple of 5> 80859095
(+1 left out) > 81869196
Multiple of 7> 778491
(+5 left out) > 828996
common total is 96
therefore, pupils in class 5B> 96  77 = 19

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Registered: 11/07/10 Posts: 70



