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Finding the Fourth Proportional to 870.02, 1,304.87 and 431.13

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Solution

The fourth proportional to 870.02, 1,304.87 and 431.13 is: 646.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    870.02 : 1,304.87 = 431.13 : x
  2. Step 2: Convert to fraction form
    870.02/1,304.87 = 431.13/x
  3. Step 3: Cross multiply
    870.02x = 1,304.87 × 431.13
  4. Step 4: Simplify right side
    870.02x = 562,568.60
  5. Step 5: Solve for x
    x = 562,568.60/870.02
  6. Step 6: Final answer
    x = 646.62

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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.