Answer:
a = 0.7 = 7/10
Step-by-step 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.
