Finding the Fourth Proportional to 138,612.80, 207,919.20 and 128,115.20
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Solution
The fourth proportional to 138,612.80, 207,919.20 and 128,115.20 is: 192,172.80
Step by Step Solution
- Step 1: Write the proportion equation
138,612.80 : 207,919.20 = 128,115.20 : x - Step 2: Convert to fraction form
138,612.80/207,919.20 = 128,115.20/x - Step 3: Cross multiply
138,612.80x = 207,919.20 × 128,115.20 - Step 4: Simplify right side
138,612.80x = 26,637,609,891.84 - Step 5: Solve for x
x = 26,637,609,891.84/138,612.80 - Step 6: Final answer
x = 192,172.80
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1.5x scale
Why These Related Problems?
These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.