Question

# The length and breadth of a rectangular field are in the ratio 4:3. Its area is 6,912m2. Find the cost of fencing at Rs. 2.50 per metre.

A
240 Rs.
No worries! We‘ve got your back. Try BYJU‘S free classes today!
B
420 Rs.
No worries! We‘ve got your back. Try BYJU‘S free classes today!
C
840 Rs.
Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses
D
1240 Rs.
No worries! We‘ve got your back. Try BYJU‘S free classes today!
Open in App
Solution

## The correct option is C 840 Rs.Given:The ratio of length and breadth of the rectangular field isl:b=4:3⇒lb=43⇒l=43b .........(1)The area of the rectangular field isl×b=6912 m2........(2)put value of l from equation (1) to equation (2)4b3×b=6912 m2⇒b2=6912×34 m2⇒b2=5184 m2⇒b=√5184 m⇒b=72 m.......(3)Put value of b from equation (3) in equation (1), we getl=43×72 m⇒l=96 m.......(4)The parameter of the rectangular field is2(l+b)=2×(96+72) m=2×168 m=336 mGiven,Cost of fencing 1 m=2.50 Rs.Hence, Cost of fencing 336 m=2.50×336 Rs.=840 Rs.Thus, Cost of fencing the rectangular field is 840 Rs.

Suggest Corrections
0
Related Videos
Area
MATHEMATICS
Watch in App
Explore more