Asked by Lluvia
Multiplying a number by 4/6 then dividing by 2/5 is the same as multiplying by what number ?
Answers
Answered by
Reiny
So what single multiplication has the same effect as
(4/6) รท (2/5) or (4/6)(5/2)
= 20/12 = 5/3
test: start with 5/7, multiply by 4/6 to give 20/42 or 10/21
now divide 10/21 by 2/5
= (10/21)(5/2) = 50/42 or 25/21
vs a single step:
(5/7)(5/3) = 25/21
remember, when we divide by a fraction we instead multiply by the reciprocal
(4/6) รท (2/5) or (4/6)(5/2)
= 20/12 = 5/3
test: start with 5/7, multiply by 4/6 to give 20/42 or 10/21
now divide 10/21 by 2/5
= (10/21)(5/2) = 50/42 or 25/21
vs a single step:
(5/7)(5/3) = 25/21
remember, when we divide by a fraction we instead multiply by the reciprocal