A field is in the shape of a trapezium having parallel sides 90 m and 30 m. These sides meet the third side at right angles .The length of the fourth side is 100 m. If it costs Rs. 4 to plough 1m2 of the field. Find the total cost of ploughing in the field.

see full answer

Your Exam Success, Personally Taken Care Of

1:1 expert mentors customize learning to your strength and weaknesses – so you score higher in school , IIT JEE and NEET entrance exams.

An Intiative by Sri Chaitanya

19200

18600

18700

14200

answer is A.

(Unlock A.I Detailed Solution for FREE)

Best Courses for You

JEE

NEET

Foundation JEE

Foundation NEET

CBSE

Detailed Solution

Let the field in the shape of a t QR and LP & LQ are 90°
Here PS=90 m, RQ=30 m, SR=100 m
Question Image

Draw a ⊥ RT from point R on to Now RT =PQ and RT॥ PQ Hence ST =90-30
=60 m
Applying pythagoras theorem in Δ
TR =√(1002-602) =√(10000-3600)=√6400=80 m
So ,the PQ = Height of the trapezium =80 m The area of the trapezium PQRS
=½ xPQ x(RQ+SP)
=½ x80x(90+30)
= 40 x 120
= 4800
Cost of ploughing 1 field = Rs. 4
∴Cost of ploughing 4800 field = 4 × 4800
=19,200

Watch 3-min video & get full concept clarity