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Finding the Fourth Proportional to 870.77, 1,306.16 and 409.07

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Solution

The fourth proportional to 870.77, 1,306.16 and 409.07 is: 613.60

Step by Step Solution

  1. Step 1: Write the proportion equation
    870.77 : 1,306.16 = 409.07 : x
  2. Step 2: Convert to fraction form
    870.77/1,306.16 = 409.07/x
  3. Step 3: Cross multiply
    870.77x = 1,306.16 × 409.07
  4. Step 4: Simplify right side
    870.77x = 534,302.30
  5. Step 5: Solve for x
    x = 534,302.30/870.77
  6. Step 6: Final answer
    x = 613.60

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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.