Question

 1     -3/5 + 7/10.       2     -7/12-8/15.      3 0,75+1/8.          4 -3  1/8-(-0,12)      5.  1,25+(-5/8)+(-5/2)

 

Answer 1

`1)-3/5+7/10`

`=-6/10+7/10`

`=1/10`

`2)-7/12-8/15`

`=-35/60-32/60`

`=-67/60`

`3)0,75+1/8`

`=3/4+1/8`

`=6/8+1/8`

`=7/8`

`4)-3 1/8-(-0,12)`

`=-3-1/8+3/25`

`=-25/8+3/25`

`=-601/200`

`5)1,25+(-5/8)+(-5/2)`

`=5/4-5/8-5/2`

`=10/8-5/8-20/8`

`=-15/8`

Answer 2

1; - \(\dfrac{3}{5}\) + \(\dfrac{7}{10}\) 

  = \(\dfrac{-6}{10}\) + \(\dfrac{7}{10}\)

  = \(\dfrac{-1}{10}\)

2; - \(\dfrac{7}{12}\) - \(\dfrac{8}{15}\)

= \(\dfrac{-35}{60}\) - \(\dfrac{32}{60}\)

= - \(\dfrac{67}{60}\)

3; 0,75 + \(\dfrac{1}{8}\)

= \(\dfrac{3}{4}\) + \(\dfrac{1}{8}\)

= \(\dfrac{6}{8}\) + \(\dfrac{1}{8}\)

= \(\dfrac{7}{8}\) 

4;   - 3\(\dfrac{1}{8}\) - (-0,12)

    = - 3,125 + 0,12

    = - 3,005

5; 1,25 + (- \(\dfrac{5}{8}\)) + (- \(\dfrac{5}{2}\))

 = 1,25 - 0,625 - 2,5

 = 0,625 - 2,5

= - 1,875