- Have any questions?
- [email protected]
- Home
- If the length and breadth of a rectangular room are each increased by 1 m, then the area of floor is increased by 21 sq.
Question 1:
If the length and breadth of a rectangular room are each increased by 1 m, then the area of floor is increased by 21 sq. m. If the length is increased by 1 m and breadth is decreased by 1 m, then the area is decreased by 5 sq. m. The perimeter of the floor is : A. 30m
B. 32m
C. 36m
D. 40m
Feedback Let length = x metres and breadth = y metres.
Then,(x+ 1) (y + 1) - xy = 21
=> x + y = 20 ...(i)
And, xy - [(x + 1)(y- 1)] = 5
<=> x - y = 6 ...(ii)
Solving (i) and (ii), we get : x = 13 and y = 7.
So, length = 13 m and breadth = 7 m.
Perimeter = [2 (13 + 7)] m = 40 m.
Then,(x+ 1) (y + 1) - xy = 21
=> x + y = 20 ...(i)
And, xy - [(x + 1)(y- 1)] = 5
<=> x - y = 6 ...(ii)
Solving (i) and (ii), we get : x = 13 and y = 7.
So, length = 13 m and breadth = 7 m.
Perimeter = [2 (13 + 7)] m = 40 m.
These questions are from this test. Would you like to take a practice test?