
By: Geeta (offline) Sunday, October 30 2011 @ 01:26 AM CDT (Read 1424 times)



Geeta 
Hi, can you please help me with this question...
The length and breadth of a rectangle are both decreaased by 20%. By how many % will its area be decreased?
Thanks in advance.
need help in this too...
How many digits are needed to form the numbers from 1  99 ?

Newbie
Registered: 12/31/06 Posts: 12





By: NQS (offline) Sunday, October 30 2011 @ 03:07 AM CDT



NQS 

Newbie
Registered: 09/16/10 Posts: 9





By: sokechan (offline) Sunday, October 30 2011 @ 03:18 AM CDT



sokechan 
36%.
Eg.
Let's assume the rectangle is referring to a square. (A sq is a rect)
Original Length > 10 cm
Area > 100 cm2
After Length > 8 cm
Area > 64 cm2
100 cm2  64 cm2 = 36cm2
36/100 * 100 = 36%
Hope this helps...
And its from the Henry Park SA2 Mathematics 2010 Paper which I just did.

Junior
Registered: 02/25/11 Posts: 23





By: NQS (offline) Sunday, October 30 2011 @ 03:20 AM CDT



NQS 

Newbie
Registered: 09/16/10 Posts: 9





By: Geeta (offline) Sunday, October 30 2011 @ 03:30 AM CDT



Geeta 
Thank u so much

Newbie
Registered: 12/31/06 Posts: 12





By: sokechan (offline) Sunday, October 30 2011 @ 04:02 AM CDT



sokechan 
1  9 > 9 digits
10  99 > 180 digits
Total > 189 digits

Junior
Registered: 02/25/11 Posts: 23





By: Geeta (offline) Sunday, October 30 2011 @ 04:48 AM CDT



Geeta 
You are too good... Thanks again...

Newbie
Registered: 12/31/06 Posts: 12



