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Finding the Fourth Proportional to 520.31, 718.65 and 380.20

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Solution

The fourth proportional to 520.31, 718.65 and 380.20 is: 525.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.31 : 718.65 = 380.20 : x
  2. Step 2: Convert to fraction form
    520.31/718.65 = 380.20/x
  3. Step 3: Cross multiply
    520.31x = 718.65 × 380.20
  4. Step 4: Simplify right side
    520.31x = 273,230.73
  5. Step 5: Solve for x
    x = 273,230.73/520.31
  6. Step 6: Final answer
    x = 525.13

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1.5x scale

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.