Đáp án:
Giải thích các bước giải:
Bài 2 :
a, 47/4 - ( 41/6 - 9/2 + 5/3 ) b, ( 47/8 - 9/4 - 0.5 ) : 75/26
= 47/4 - ( 7/3 + 5/3 ) = ( 47/8 - 9/4 - 1/2 ) : 75/26
= 47/4 - 4 = 31/4 = (29/8 - 1/2 ) : 75/26
= 25/8 : 75/26 = 13/12
c, ( 268/15 - 24/7 ) - ( 42/15 - 4 ) d, 8/3 . (-4/5) . 0,375 . (-10) . (-15/24)
= 1516/105 + 6/5 = 1642/105 = 8/3 . (-4/5) . 3/8 . (-10) . (-5/8)
= -32/15 . 3/8 . (-10) . (-5/8)
= -4/5 . (-10) . (-5/8)
= 8 . (-5/8) = -5
Bài 3 :
a, 5 : 3/4 - 24/5 : 3/4 b, -3/5 . 2/7 + (-3/7) . (-3/5) + (-3/7)
= 20/3 - 32/5 = 4/15 = -3/5 . ( -3/7 + 2/7 ) + (-3/7)
= -3/5 . (-1/7) + (-3/7)
= 3/35 + (-3/7) = -12/35
c, ( -30/7 . 7/11 + 7/11 . 16/3 ) . 5 - 17/3 d, 5/39 . ( 39/5 . 5/3 + 25/3 . 39/5 )
= ( -30/11 + 112/33 ) . 5 - 17/3 = 5/39 . ( 13 + 65 )
= 2/3 . 5 - 17/3 = 5/39 . 78 = 10
= 10/3 - 17/3 = -7/3
Bài 4 :
a, 37/7 . 8/11 + 37/7 . 5/11 - 37/7 . 2/11
= 37/7 . ( 8/11 + 5/11 - 2/11 )
= 37/7 . ( 13/11 - 2/11 )
= 37/7 . 1 = 37/7
