Solve 1/2*(20/21+5/11)

$$\frac{ 1 }{ 2 } \times ( \frac{ 20 }{ 21 } + \frac{ 5 }{ 11 } )$$

Evaluate

$$\frac{325}{462}\approx 0.703463203$$

Solution Steps

Least common multiple of 21 and 11 is 231. Convert \frac{20}{21} and \frac{5}{11} to fractions with denominator 231.

$$\frac{1}{2}\left(\frac{220}{231}+\frac{105}{231}\right)$$

Since \frac{220}{231} and \frac{105}{231} have the same denominator, add them by adding their numerators.

$$\frac{1}{2}\times \frac{220+105}{231}$$

Add 220 and 105 to get 325.

$$\frac{1}{2}\times \frac{325}{231}$$

Multiply \frac{1}{2} times \frac{325}{231} by multiplying numerator times numerator and denominator times denominator.

$$\frac{1\times 325}{2\times 231}$$

Do the multiplications in the fraction \frac{1\times 325}{2\times 231}.

$$\frac{325}{462}$$

Factor

$$\frac{5 ^ {2} \cdot 13}{2 \cdot 3 \cdot 7 \cdot 11} = 0.7034632034632035$$