Question

tengo que resolver esto ayudenme

a) 7/4 + 7/8 - 5/2

b) 5/3 + 1/2 +3/4

c) 8/5 - (17/10 - 3/2)

d) 3/7 - (5/21 + 1/14)

Answer 1

$\frac{7}{4}+\frac{7}{8}-\frac{5}{2}$
$=\frac{7\cdot \:2}{8}+\frac{7}{8}-\frac{5\cdot \:4}{8}$
$=\frac{2\cdot \:7+7-4\cdot \:5}{8}$
$=\frac{1}{8}$


$\frac{5}{3}+\frac{1}{2}+\frac{3}{4}$
$=\frac{5\cdot \:4}{12}+\frac{6}{12}+\frac{3\cdot \:3}{12}$
$=\frac{4\cdot \:5+6+3\cdot \:3}{12}$
$=\frac{35}{12}$


$\frac{8}{5}-\left(\frac{17}{10}-\frac{3}{2}\right)$
$=\frac{8}{5}-\frac{1}{5}$
$=\frac{8-1}{5}$
$=\frac{7}{5}$


$\frac{3}{7}-\left(\frac{5}{21}+\frac{1}{14}\right)$
$=\frac{3}{7}-\frac{13}{42}$
$=\frac{3\cdot \:6}{42}-\frac{13}{42}$
$=\frac{3\cdot \:6-13}{42}$
$=\frac{5}{42}$