Question

The value of $10\frac{1}{2}\times 16\frac{1}{5}$ calculated using binomial expansion is

• A. $170\frac{1}{5}$
• B. $170\frac{1}{10}$
• C. $180\frac{1}{5}$
• D. $180\frac{1}{10}$

Answer 1

The correct option is B

$170\frac{1}{10}$

$10\frac{1}{2}\times 16\frac{1}{5}$ can be written as

$(10+\frac{1}{2})(16+\frac{1}{5})$

$=10\times 16+10\times \frac{1}{5}+\frac{1}{2}\times 16+\frac{1}{2}\times \frac{1}{5}$

$=160+2+8+\frac{1}{10}$

$=170\frac{1}{10}$