Finding the Fourth Proportional to 815, 1,124.70 and 447
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Solution
The fourth proportional to 815, 1,124.70 and 447 is: 616.86
Step by Step Solution
- Step 1: Write the proportion equation
815 : 1,124.70 = 447 : x - Step 2: Convert to fraction form
815/1,124.70 = 447/x - Step 3: Cross multiply
815x = 1,124.70 × 447 - Step 4: Simplify right side
815x = 502,740.90 - Step 5: Solve for x
x = 502,740.90/815 - Step 6: Final answer
x = 616.86
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Why These Related Problems?
These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.