Solve 5/21*15/7+2/4*3/7

$$\frac { 5 } { 21 } \times 1 \frac { 5 } { 7 } + \frac { 2 } { 4 } \times \frac { 3 } { 7 }$$

Evaluate

$$\frac{61}{98}\approx 0.62244898$$

Solution Steps

Multiply 1 and 7 to get 7.

$$\frac{5}{21}\times \frac{7+5}{7}+\frac{2}{4}\times \frac{3}{7}$$

Add 7 and 5 to get 12.

$$\frac{5}{21}\times \frac{12}{7}+\frac{2}{4}\times \frac{3}{7}$$

Multiply \frac{5}{21} times \frac{12}{7} by multiplying numerator times numerator and denominator times denominator.

$$\frac{5\times 12}{21\times 7}+\frac{2}{4}\times \frac{3}{7}$$

Do the multiplications in the fraction \frac{5\times 12}{21\times 7}.

$$\frac{60}{147}+\frac{2}{4}\times \frac{3}{7}$$

Reduce the fraction \frac{60}{147} to lowest terms by extracting and canceling out 3.

$$\frac{20}{49}+\frac{2}{4}\times \frac{3}{7}$$

Reduce the fraction \frac{2}{4} to lowest terms by extracting and canceling out 2.

$$\frac{20}{49}+\frac{1}{2}\times \frac{3}{7}$$

Multiply \frac{1}{2} times \frac{3}{7} by multiplying numerator times numerator and denominator times denominator.

$$\frac{20}{49}+\frac{1\times 3}{2\times 7}$$

Do the multiplications in the fraction \frac{1\times 3}{2\times 7}.

$$\frac{20}{49}+\frac{3}{14}$$

Least common multiple of 49 and 14 is 98. Convert \frac{20}{49} and \frac{3}{14} to fractions with denominator 98.

$$\frac{40}{98}+\frac{21}{98}$$

Since \frac{40}{98} and \frac{21}{98} have the same denominator, add them by adding their numerators.

$$\frac{40+21}{98}$$

Add 40 and 21 to get 61.

$$\frac{61}{98}$$

Factor

$$\frac{61}{2 \cdot 7 ^ {2}} = 0.6224489795918368$$