Question

Tính nhanh:

a) [(-50,17) . 0,2 + (-9,83) . 0,2] : 0,2

b) [(-30,17) . 0,2 + (-9,83) . 0,2] - [4,48 - (-2,52)] : 0,4

Answer 1

a)\(\left[\left(-50,17\right).0,2+\left(-9,83\right).0,2\right]:0,2\)

=\(\left[\left[\left(-50,17\right)+\left(-9,83\right)\right].0,2\right]:0.2\)

=\(\left[\left(-60\right).0,2\right]:0,2\)

=\(\left(-12\right):0,2\)

=\(-60\)

b)\(\left[\left(-30,17\right).0,2+\left(-9,83\right).0,2\right]-\left[4,48-\left(-2,52\right)\right]:0,4\)

=\(\left\{\left[\left(-30,17\right)+\left(-9,83\right)\right].0,2\right\}-\left(4,48+2,52\right):0,4\)

=\(\left[\left(-40\right).0,2\right]-7:0,4\)

=\(\left(-8\right)-17,5\)

=\(-25,5\)