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0.7 of what number is 4 1/2?​

User Wajax
by
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1 Answer

4 votes

Answer:

x = 45/7

Explanation:

Write as an algebraic equation.

Look at each part in the word question : 0.7 of what number is 4 1/2

"0.7 of what number" can be written as 0.7x

The word "is" means equals.

0.7x = 4 1/2 <= The equation, using 'x' to represent the number.

To find the number, isolate 'x'.

0.7x =
4(1)/(2) Convert mixed fraction to improper fraction

0.7x =
((4*2)+1)/(2) Multiply the whole number by the denominator and add it to the numerator

0.7x =
(9)/(2) Now isolate 'x'

0.7x/0.7 =
(9)/(2)/0.7 Divide both sides by 0.7

x =
(9)/(2)/0.7 Simplify right side

x =
(9)/(2)/(7)/(10) Rewrite 0.7 as a fraction

x =
(9)/(2)*(10)/(7) To divide, you multiply a flipped fraction

x =
(9*10)/(2*7) Multiply across the top and across the bottom

x = 90/14 Reduce to lowest terms. Top and bottom are divisible by 2

x = 45/7 Answer

User Vlad Tarniceru
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4.8k points