Решите срочна математикк

Question

Решите срочна математикк

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Answer 1

3)
 9/20*2/3+5/14*7/25=  3/10+1/10= 4/10= 2/5= 0,4
4) 15/4*2/5-81/25*5/27= 3/2-3/5= 15/10-6/10= 9/10= 0,9

Comments

1) 5/6*9/15-5/12*4/15= 2-1/9= 1 9/9-1/9= 18/9-1/9= 17/9= 1целая8/9

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2) 7/18*9/14+1/3*6/7= 1/4+2/7= 7/14+4/14= 11/14