1. 5(-3 + 2) – 7. (5 – 4) 2. 3.(-5 + 6) – 4.(3 – 2) 4.1975.(-115) + 1975.15 6. 157.17 – 157 . 7 8. -39.(5 – 99)+99.(10 – 39) 10. (-37).86 + 37. 76 3. 17.(-84) + 17.(-16) 5. -145.(13 – 57) + 57(10 – 145) 7. 199.(15 – 17) – 199. (-17+5) 9. -38.(25 – 4) + 25.(-4 + 38)

1) 5.(-3+2)-7.(5-4)

=5.(-1)-7.1

=(-5).1-7.1

=1.[(-5)-7]

=1.(-12)

=-12

2) 3.(-5 + 6) – 4.(3 – 2)

=3.1-4.1

=3-4

=-1

3) 17.(-84) + 17.(-16)

=17.{(-84)+(-16)}

=17.(-100)

=-1700

4) 1975.(-115) + 1975.15

=1975.{(-115)+15}

=1975.(-100)

=-197500

5) -145.(13 – 57) + 57(10 – 145)

=-145.(-44)+57.(-15)

=6380-7695

=1315

6) 157.17 – 157 . 7

=157.(17-7)

=157.10

=1570

7) 199.(15 – 17) – 199. (-17+5)

=199.(-2)-199.(-12)

=199.{(-2)-(-12)}

=199.10

=1990

8) -39.(5 – 99)+99.(10 – 39)

=-39.(-94)+99.(-29)

=3666+(-2871)

=795

9) -38.(25 – 4) + 25.(-4 + 38)

=-38.21+25.34

=-798+850

=52

10) (-37).86 + 37. 76

=37.(-86)+37.76

=37.{(-86)+76}

=37.(-10)

=-370

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