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Finding the Fourth Proportional to 870.02, 1,200.64 and 520.64

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Solution

The fourth proportional to 870.02, 1,200.64 and 520.64 is: 718.49

Step by Step Solution

  1. Step 1: Write the proportion equation
    870.02 : 1,200.64 = 520.64 : x
  2. Step 2: Convert to fraction form
    870.02/1,200.64 = 520.64/x
  3. Step 3: Cross multiply
    870.02x = 1,200.64 × 520.64
  4. Step 4: Simplify right side
    870.02x = 625,101.21
  5. Step 5: Solve for x
    x = 625,101.21/870.02
  6. Step 6: Final answer
    x = 718.49

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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.