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Finding the Fourth Proportional to 870.18, 1,306 and 480.54

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Solution

The fourth proportional to 870.18, 1,306 and 480.54 is: 721.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    870.18 : 1,306 = 480.54 : x
  2. Step 2: Convert to fraction form
    870.18/1,306 = 480.54/x
  3. Step 3: Cross multiply
    870.18x = 1,306 × 480.54
  4. Step 4: Simplify right side
    870.18x = 627,585.24
  5. Step 5: Solve for x
    x = 627,585.24/870.18
  6. Step 6: Final answer
    x = 721.21

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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.