R-SAT
Exam
Numerical Ability
Quadratic Equations
A rectangle plot was fenced without idea of its actual measurements . When measurements were known then it was found to have lost 20% of its length and 10% of its breadth. The Percentage of decrease in area is ?
Option
a) 28%
b) 18%
c) 13%
d) 26%
e) None
Read Solution (Total 7)
-
- formula is = x + y + xy/100 but lost
-20-10 + ((-10)*(-20))/100
-30 + 2
-28%
28 % decreses - 10 years agoHelpfull: Yes(4) No(0)
- new length = 4/5 x
new breadth = 9/10 y
area = xy
new area = 36/50 xy
percent loss in area = {1-(36/50)}/100
= 28% - 10 years agoHelpfull: Yes(3) No(0)
- 28% is the answer
let us have the initial area xy
new area becomes 36/50xy which is 72% of original area. so,there is a lose in 28%.
- 10 years agoHelpfull: Yes(0) No(0)
- (a)28%
Using Formula,
X+Y+XY/100
-20-10+((-10)*(-20))/100
-30+200/100
-30+2
-28
i.e. 28% loss or decrease - 9 years agoHelpfull: Yes(0) No(0)
- let length be x and breadth be y
then area=xy
x-20%ofx=4x/5
y-10%ofy=9y/10
area=36xy/50
then after dividing we get 72%
so 100-72=28%
- 9 years agoHelpfull: Yes(0) No(0)
- ans a is correct
- 9 years agoHelpfull: Yes(0) No(0)
- a.28%
assume total 100
length has lost of 20% =80% and now10% on 80% we get 72% which is 100-72=28% - 7 years agoHelpfull: Yes(0) No(0)
R-SAT Other Question