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Finding the Fourth Proportional to 870.20, 1,201.04 and 520.80

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Solution

The fourth proportional to 870.20, 1,201.04 and 520.80 is: 718.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    870.20 : 1,201.04 = 520.80 : x
  2. Step 2: Convert to fraction form
    870.20/1,201.04 = 520.80/x
  3. Step 3: Cross multiply
    870.20x = 1,201.04 × 520.80
  4. Step 4: Simplify right side
    870.20x = 625,501.63
  5. Step 5: Solve for x
    x = 625,501.63/870.20
  6. Step 6: Final answer
    x = 718.80

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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.