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Finding the Fourth Proportional to 520.90, 718.90 and 380.95

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Solution

The fourth proportional to 520.90, 718.90 and 380.95 is: 525.75

Step by Step Solution

  1. Step 1: Write the proportion equation
    520.90 : 718.90 = 380.95 : x
  2. Step 2: Convert to fraction form
    520.90/718.90 = 380.95/x
  3. Step 3: Cross multiply
    520.90x = 718.90 × 380.95
  4. Step 4: Simplify right side
    520.90x = 273,864.96
  5. Step 5: Solve for x
    x = 273,864.96/520.90
  6. Step 6: Final answer
    x = 525.75

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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.