Solve (0.3div21/10-1/14)*2.8

$$(0.3 \div 2 \frac { 1 } { 10 } - \frac{ 1 }{ 14 } ) \times 2.8$$

Evaluate

$$0.2$$

Solution Steps

Divide 0.3 by \frac{2\times 10+1}{10} by multiplying 0.3 by the reciprocal of \frac{2\times 10+1}{10}.

$$\left(\frac{0.3\times 10}{2\times 10+1}-\frac{1}{14}\right)\times 2.8$$

Multiply 0.3 and 10 to get 3.

$$\left(\frac{3}{2\times 10+1}-\frac{1}{14}\right)\times 2.8$$

Multiply 2 and 10 to get 20.

$$\left(\frac{3}{20+1}-\frac{1}{14}\right)\times 2.8$$

Add 20 and 1 to get 21.

$$\left(\frac{3}{21}-\frac{1}{14}\right)\times 2.8$$

Reduce the fraction \frac{3}{21} to lowest terms by extracting and canceling out 3.

$$\left(\frac{1}{7}-\frac{1}{14}\right)\times 2.8$$

Least common multiple of 7 and 14 is 14. Convert \frac{1}{7} and \frac{1}{14} to fractions with denominator 14.

$$\left(\frac{2}{14}-\frac{1}{14}\right)\times 2.8$$

Since \frac{2}{14} and \frac{1}{14} have the same denominator, subtract them by subtracting their numerators.

$$\frac{2-1}{14}\times 2.8$$

Subtract 1 from 2 to get 1.

$$\frac{1}{14}\times 2.8$$

Convert decimal number 2.8 to fraction \frac{28}{10}. Reduce the fraction \frac{28}{10} to lowest terms by extracting and canceling out 2.

$$\frac{1}{14}\times \frac{14}{5}$$

Multiply \frac{1}{14} times \frac{14}{5} by multiplying numerator times numerator and denominator times denominator.

$$\frac{1\times 14}{14\times 5}$$

Cancel out 14 in both numerator and denominator.

$$\frac{1}{5}$$

Factor

$$\frac{1}{5} = 0.2$$