Solve (3/16-0.45)*0.8-0.21:0.2

$$( \frac { 3 } { 16 } - 0.45 ) \cdot 0.8 - 0.21 : 0.2$$

Evaluate

$$-1.26$$

Solution Steps

Convert decimal number 0.45 to fraction \frac{45}{100}. Reduce the fraction \frac{45}{100} to lowest terms by extracting and canceling out 5.

$$\left(\frac{3}{16}-\frac{9}{20}\right)\times 0.8-\frac{0.21}{0.2}$$

Least common multiple of 16 and 20 is 80. Convert \frac{3}{16} and \frac{9}{20} to fractions with denominator 80.

$$\left(\frac{15}{80}-\frac{36}{80}\right)\times 0.8-\frac{0.21}{0.2}$$

Since \frac{15}{80} and \frac{36}{80} have the same denominator, subtract them by subtracting their numerators.

$$\frac{15-36}{80}\times 0.8-\frac{0.21}{0.2}$$

Subtract 36 from 15 to get -21.

$$-\frac{21}{80}\times 0.8-\frac{0.21}{0.2}$$

Convert decimal number 0.8 to fraction \frac{8}{10}. Reduce the fraction \frac{8}{10} to lowest terms by extracting and canceling out 2.

$$-\frac{21}{80}\times \frac{4}{5}-\frac{0.21}{0.2}$$

Multiply -\frac{21}{80} times \frac{4}{5} by multiplying numerator times numerator and denominator times denominator.

$$\frac{-21\times 4}{80\times 5}-\frac{0.21}{0.2}$$

Do the multiplications in the fraction \frac{-21\times 4}{80\times 5}.

$$\frac{-84}{400}-\frac{0.21}{0.2}$$

Reduce the fraction \frac{-84}{400} to lowest terms by extracting and canceling out 4.

$$-\frac{21}{100}-\frac{0.21}{0.2}$$

Expand \frac{0.21}{0.2} by multiplying both numerator and the denominator by 100.

$$-\frac{21}{100}-\frac{21}{20}$$

Least common multiple of 100 and 20 is 100. Convert -\frac{21}{100} and \frac{21}{20} to fractions with denominator 100.

$$-\frac{21}{100}-\frac{105}{100}$$

Since -\frac{21}{100} and \frac{105}{100} have the same denominator, subtract them by subtracting their numerators.

$$\frac{-21-105}{100}$$

Subtract 105 from -21 to get -126.

$$\frac{-126}{100}$$

Reduce the fraction \frac{-126}{100} to lowest terms by extracting and canceling out 2.

$$-\frac{63}{50}$$

Factor

$$-1.26$$