Solve 7/20-5/7-3/2-1/3=

$$\frac { 7 } { 20 } - \frac { 5 } { 7 } - \frac { 3 } { 2 } - \frac { 1 } { 3 } =$$

Evaluate

$$-\frac{923}{420}\approx -2.197619048$$

Solution Steps

Least common multiple of 20 and 7 is 140. Convert \frac{7}{20} and \frac{5}{7} to fractions with denominator 140.

$$\frac{49}{140}-\frac{100}{140}-\frac{3}{2}-\frac{1}{3}$$

Since \frac{49}{140} and \frac{100}{140} have the same denominator, subtract them by subtracting their numerators.

$$\frac{49-100}{140}-\frac{3}{2}-\frac{1}{3}$$

Subtract 100 from 49 to get -51.

$$-\frac{51}{140}-\frac{3}{2}-\frac{1}{3}$$

Least common multiple of 140 and 2 is 140. Convert -\frac{51}{140} and \frac{3}{2} to fractions with denominator 140.

$$-\frac{51}{140}-\frac{210}{140}-\frac{1}{3}$$

Since -\frac{51}{140} and \frac{210}{140} have the same denominator, subtract them by subtracting their numerators.

$$\frac{-51-210}{140}-\frac{1}{3}$$

Subtract 210 from -51 to get -261.

$$-\frac{261}{140}-\frac{1}{3}$$

Least common multiple of 140 and 3 is 420. Convert -\frac{261}{140} and \frac{1}{3} to fractions with denominator 420.

$$-\frac{783}{420}-\frac{140}{420}$$

Since -\frac{783}{420} and \frac{140}{420} have the same denominator, subtract them by subtracting their numerators.

$$\frac{-783-140}{420}$$

Subtract 140 from -783 to get -923.

$$-\frac{923}{420}$$

Factor

$$-\frac{923}{420} = -2\frac{83}{420} = -2.197619047619048$$