Question

Exercițiul 15 va rog dau coroana

Answer 1

a)

$- \frac{2}{7} - ( - \frac{5}{7} ) = \\ = - \frac{2}{7} + \frac{5}{7} = \\ = + \frac{3}{7}$

b)

$- \frac{4}{3} - ( + \frac{70}{3} ) = \\ = - \frac{4}{3} - \frac{70}{3} = \\ = - \frac{74}{3}$

c)

$\frac{9}{4} - ( - \frac{3}{4} ) = \\ = \frac{9}{4} + \frac{3}{4} = \\ = \frac{12}{4}$

d)

$+ \frac{1}{3} - ( + \frac{1}{6} ) = \\ = \frac{2}{6} - \frac{1}{6} = \\ = \frac{1}{6}$

e)

$- \frac{2}{5} - ( - \frac{7}{10} ) = \\ = - \frac{4}{10} + \frac{7}{10} = \\ = + \frac{3}{10}$

f)

$\frac{5}{12} - ( - \frac{1}{6} ) = \\ = \frac{5}{12} + \frac{2}{12} = \\ = \frac{7}{12}$

g)

$- \frac{1}{24} - ( + \frac{9}{8} ) = \\ = - \frac{1}{24} - \frac{27}{24} = \\ = - \frac{28}{24}$

h)

$4.5 - (4.5 - 3) = \\ = 4.5 - 1.5 = \\ = 3$

i)

$- 7.7 - ( - 2.8) - 9 = \\ = - 7.7 + 2.8 - 9 = \\ = - 4.9 - 9 = \\ = - 13.9$