Question

add.(7) $\frac{1}{4}+\frac{1}{8}+\frac{1}{10}$=(8) $\frac{1}{5}+\frac{1}{6}+\frac{1}{15}$=(9) $\frac{1}{6}+\frac{1}{9}+\frac{1}{12}$=(10) $\frac{1}{7}+\frac{1}{8}+\frac{1}{14}$=(11) $\frac{1}{8}+\frac{1}{9}+\frac{1}{24}$=(12) $\frac{1}{9}+\frac{1}{10}+\frac{1}{30}$=

Explanation:

(7) Step1: Find least common denominator (LCD=40)

$\frac{1}{4} + \frac{1}{8} + \frac{1}{10} = \frac{10}{40} + \frac{5}{40} + \frac{4}{40}$

(7) Step2: Sum the numerators

$\frac{10+5+4}{40} = \frac{19}{40}$

(8) Step1: Find LCD=30

$\frac{1}{5} + \frac{1}{6} + \frac{1}{15} = \frac{6}{30} + \frac{5}{30} + \frac{2}{30}$

(8) Step2: Sum the numerators

$\frac{6+5+2}{30} = \frac{13}{30}$

(9) Step1: Find LCD=36

$\frac{1}{6} + \frac{1}{9} + \frac{1}{12} = \frac{6}{36} + \frac{4}{36} + \frac{3}{36}$

(9) Step2: Sum the numerators

$\frac{6+4+3}{36} = \frac{13}{36}$

(10) Step1: Find LCD=56

$\frac{1}{7} + \frac{1}{8} + \frac{1}{14} = \frac{8}{56} + \frac{7}{56} + \frac{4}{56}$

(10) Step2: Sum the numerators

$\frac{8+7+4}{56} = \frac{19}{56}$

(11) Step1: Find LCD=72

$\frac{1}{8} + \frac{1}{9} + \frac{1}{24} = \frac{9}{72} + \frac{8}{72} + \frac{3}{72}$

(11) Step2: Sum the numerators

$\frac{9+8+3}{72} = \frac{20}{72} = \frac{5}{18}$

(12) Step1: Find LCD=90

$\frac{1}{9} + \frac{1}{10} + \frac{1}{30} = \frac{10}{90} + \frac{9}{90} + \frac{3}{90}$

(12) Step2: Sum the numerators

$\frac{10+9+3}{90} = \frac{22}{90} = \frac{11}{45}$

Answer:

(7) $\frac{19}{40}$
(8) $\frac{13}{30}$
(9) $\frac{13}{36}$
(10) $\frac{19}{56}$
(11) $\frac{5}{18}$
(12) $\frac{11}{45}$