proportion question?????

Question

is a/b = c/d proportional to (a+b)/b = (c + d)/d ?? prove your answer.

Answer 1

I would say yes:
(a+b) / b = (c+d) / d
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By cross multiplying you get: (a+b)d = (c+d)b
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By factoring in the variables you get: ad+bd = cb+db
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By dividing by d you get: a+b= (cb/d) + b
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Next you subtract the b from the right side giving you: a = (cb/d)
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Lastly by multiplying the right side by the reciprocal of 1/b you will be left with: (a/b) = (c/d)
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Either method between the first person's answer and mine works, so...I hope this helps and good luck!

Answer 2

(a + b) / b = a/b + 1
(c + d) / d = c/d + 1
If (a + b) / b = (c + d)/d then:-
a/b + 1 = c/d + 1
a/b = c/d
Answer is YES

Answer 3

yes!!!

a/b = c/d

add 1 for both sides
a/b + 1 = c/d + 1

a/b + b/b = c/d + d/d

(a+b)/b = (c+d)/d