
By: geniuskids (offline) Monday, April 29 2013 @ 11:10 AM CDT (Read 842 times)



geniuskids 
Hi there, kindly help with these questions:
(Q12) There are 40 pupils in a class. 15 of them are girls. How many percent more boys than girls are there?
(1) 10%
(2) 25%
(3) 33 2/3%
(4) 66 2/3%
Answer from the answer sheet is (4).
I'm puzzled!
(Q20) Pls refer to the diagram on the test paper. However I did not upload. Pls help solve if you have the diagram. tks

Active Member
Registered: 11/12/11 Posts: 169





By: echeewh (offline) Monday, April 29 2013 @ 04:45 PM CDT



echeewh 
Hey Geniuskids,
Following pls find my worked solutions:
Q12
Required % = [(B  G) / G] × 100
B = 40  15 = 25
Required % = [(25  15) / 15] × 100
= (10 / 15) × 100
= (2 / 3) × 100
= 200 / 3
= 66 2/3 %
=========
Q20
Join OM (the other diagonal of the square MNOP).
Length of OM = NP
OM is also the radius of Quadrant TSO.
Radius OM = OS = (x + 3)
Hence, NP = (x + 3) cm
=========
Trust this helps.
Do let me know again if there's further clarification.
Cheer,
Edward

Active Member
Registered: 04/21/11 Posts: 627





By: echeewh (offline) Monday, April 29 2013 @ 04:45 PM CDT



echeewh 
Hey Geniuskids,
Following pls find my worked solutions:
Q12
Required % = [(B  G) / G] × 100
B = 40  15 = 25
Required % = [(25  15) / 15] × 100
= (10 / 15) × 100
= (2 / 3) × 100
= 200 / 3
= 66 2/3 %
=========
Q20
Join OM (the other diagonal of the square MNOP).
Length of OM = NP
OM is also the radius of Quadrant TSO.
Radius OM = OS = (x + 3)
Hence, NP = (x + 3) cm
=========
Trust this helps.
Do let me know again if there's further clarification.
Cheer,
Edward

Active Member
Registered: 04/21/11 Posts: 627



