Question

Please dont give a useless answer

Answer 1

`(7)/(10) ,0.7`

Reasoning:

Do the inverse of adding 4/5 to isolate and find a.

`1(1)/(2) - (4)/(5) =(7)/(10)`

Decimal Form:

`1.5-0.8=0.7`

Answer 2

a = 0.7 = 7/10

Explanation:

Subtract 4/5 from both sides.

a + 4/5 = 1 1/2

a + 0.8 = 1.5

a + 0.8 -0.8 = 1.5 -0.8 . . . . subtract 4/5 from both sides

a = 0.7 = 7/10

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If you like, you can solve this a couple of other ways:

1) Solve it as an integer problem.

10a +8 = 15 . . . . . . multiply the given equation by 10 to clear fractions

10a = 7 . . . . . . . . subtract 8

a = 7/10 . . . . . . divide by 10

2) Use a common denominator

a +8/10 = 1 5/10

a = 1 5/10 -8/10 . . . . . subtract 8/10

a = 15/10 -8/10 = (15 -8)/10 = 7/10 . . . . . convert to improper fraction

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Additional comment

It is a good idea to get comfortable working with numbers in any form in which they are presented: decimal, fraction, mixed number, scientific notation, percentage. Knowing how to convert between forms is essential.