Finding the Fourth Proportional to 128,612.20, 192,918.30 and 86,621.80
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Solution
The fourth proportional to 128,612.20, 192,918.30 and 86,621.80 is: 129,932.70
Step by Step Solution
- Step 1: Write the proportion equation
128,612.20 : 192,918.30 = 86,621.80 : x - Step 2: Convert to fraction form
128,612.20/192,918.30 = 86,621.80/x - Step 3: Cross multiply
128,612.20x = 192,918.30 × 86,621.80 - Step 4: Simplify right side
128,612.20x = 16,710,930,398.94 - Step 5: Solve for x
x = 16,710,930,398.94/128,612.20 - Step 6: Final answer
x = 129,932.70
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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.