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Finding the Fourth Proportional to 630.79, 870.72 and 409.66

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Solution

The fourth proportional to 630.79, 870.72 and 409.66 is: 565.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    630.79 : 870.72 = 409.66 : x
  2. Step 2: Convert to fraction form
    630.79/870.72 = 409.66/x
  3. Step 3: Cross multiply
    630.79x = 870.72 × 409.66
  4. Step 4: Simplify right side
    630.79x = 356,695.44
  5. Step 5: Solve for x
    x = 356,695.44/630.79
  6. Step 6: Final answer
    x = 565.48

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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.