简算难题,:24×205 672­­‐36﹢64 25+75‐25+75 5+263+55-198
2个回答

24×205

=24×(200+5)

=4800+120

=4920

672­­‐36﹢64

=672+(64-36)

=672+28

=700

25+75‐25+75

=75+75+25-25

=75+75

=150

5+263+55-198

=268-198+55

=70+55

=125

87-187-139-61

=87-187-(139+61)

=-100-200

=-300

1280÷16÷8

=1280÷(16×8)

=1280÷128

=10

8×125 =1000

(125+70)×8

=125×8+70×8

=1000+560

=1560

4004×25

=(4000+4)×25

=100000+100

=100100