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Finding the Fourth Proportional to 486.61, 728.53 and 388.18

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Solution

The fourth proportional to 486.61, 728.53 and 388.18 is: 581.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    486.61 : 728.53 = 388.18 : x
  2. Step 2: Convert to fraction form
    486.61/728.53 = 388.18/x
  3. Step 3: Cross multiply
    486.61x = 728.53 × 388.18
  4. Step 4: Simplify right side
    486.61x = 282,800.78
  5. Step 5: Solve for x
    x = 282,800.78/486.61
  6. Step 6: Final answer
    x = 581.17

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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.