Question

Number of rectangles in figure shown which are not square is

• A. $170$
• B. $160$
• C. $161$
• D. $Noneofthese$

Answer 1

The correct option is A $170$

To find number of rectangle

number of rectangle $=m\frac{(m+1)}{2}\cdot n\frac{(n+1)}{2}$

$=4\times \frac{5}{2}\times 6\times \frac{7}{2}$

$=210$

Number of square $=n\times m+(n-1)(m-1)+(n-2)(m-2)+(n-3)(m-3)$

$=6\times 4+5\times 3+4\times 2+3\times 1$

$=40$

Rectangles which are not squares$210-40=170$

Answer