Solve 21/5+3/4+31/2=

$$2 \frac { 1 } { 5 } + \frac { 3 } { 4 } + 3 \frac { 1 } { 2 } =$$

Evaluate

$$\frac{129}{20}=6.45$$

Solution Steps

Multiply 2 and 5 to get 10.

$$\frac{10+1}{5}+\frac{3}{4}+\frac{3\times 2+1}{2}$$

Add 10 and 1 to get 11.

$$\frac{11}{5}+\frac{3}{4}+\frac{3\times 2+1}{2}$$

Least common multiple of 5 and 4 is 20. Convert \frac{11}{5} and \frac{3}{4} to fractions with denominator 20.

$$\frac{44}{20}+\frac{15}{20}+\frac{3\times 2+1}{2}$$

Since \frac{44}{20} and \frac{15}{20} have the same denominator, add them by adding their numerators.

$$\frac{44+15}{20}+\frac{3\times 2+1}{2}$$

Add 44 and 15 to get 59.

$$\frac{59}{20}+\frac{3\times 2+1}{2}$$

Multiply 3 and 2 to get 6.

$$\frac{59}{20}+\frac{6+1}{2}$$

Add 6 and 1 to get 7.

$$\frac{59}{20}+\frac{7}{2}$$

Least common multiple of 20 and 2 is 20. Convert \frac{59}{20} and \frac{7}{2} to fractions with denominator 20.

$$\frac{59}{20}+\frac{70}{20}$$

Since \frac{59}{20} and \frac{70}{20} have the same denominator, add them by adding their numerators.

$$\frac{59+70}{20}$$

Add 59 and 70 to get 129.

$$\frac{129}{20}$$

Factor

$$\frac{3 \cdot 43}{2 ^ {2} \cdot 5} = 6\frac{9}{20} = 6.45$$