A = original number of kilograms = 45
B = original number of pounds (corresponding to A) = 100
C = new number of kilograms = unknown (call it x for now)
D = new number of pounds (corresponding to C) = 70
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So in short we have: A = 45, B = 100, C = x, D = 70. We can set up the proportion below and solve for x
A/B = C/D
45/100 = x/70
0.45 = x/70
x/70 = 0.45
x = 70*0.45 <<--- multiply both sides by 70
x = 31.5
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Final Answer: 31.5 kilograms corresponds to 100 pounds
