Mensuration Ques 43
Question
One side of a rectangular ground is 8 metre and its diagonal is 17 metre. Another rectangular ground 16 metre long and 10 metre broad has a concrete path 2.5 metre wide all around it on the outside. What is the difference between the areas of the first ground and the path in second ground?
(1) $39 m^{2}$
(2) $31 m^{2}$
(3) $35 m^{2}$
(4) $37 m^{2}$
(5) $33 m^{2}$
(IBPS Bank PO/MT CWE (Main Exam) 30.11.2019)
Show Answer
Correct Answer: (3)
Solution: (3)
For the first ground,
$d=\sqrt{\left(l^{2}+b^{2}\right)}$
$\Rightarrow 17=\sqrt{\left(l^{2}+8^{2}\right)}$
$\Rightarrow l^{2}=17^{2}-8^{2}$
$\Rightarrow l=289-64=225$
$\Rightarrow l=\sqrt{225}=15$ metre
$\therefore$ Area $=15 \times 8$ $=120$ sq. metre
For the second ground,
Area of ground without path $=16 \times 10=160$ sq. metre
Total area (ground + path) $=(16+5) \times(10+5)$
$=21 \times 15$ $=315$ sq. metre
Area of path $=315-160$ $=155$ sq. metre
Required difference $=155-120=35$ sq. metre
BETA
