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Finding the Fourth Proportional to 520.89, 718.18 and 380.90

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Solution

The fourth proportional to 520.89, 718.18 and 380.90 is: 525.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.89 : 718.18 = 380.90 : x
  2. Step 2: Convert to fraction form
    520.89/718.18 = 380.90/x
  3. Step 3: Cross multiply
    520.89x = 718.18 × 380.90
  4. Step 4: Simplify right side
    520.89x = 273,550.22
  5. Step 5: Solve for x
    x = 273,550.22/520.89
  6. Step 6: Final answer
    x = 525.16

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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.