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Finding the Fourth Proportional to 634.79, 875.80 and 398.95

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Solution

The fourth proportional to 634.79, 875.80 and 398.95 is: 550.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    634.79 : 875.80 = 398.95 : x
  2. Step 2: Convert to fraction form
    634.79/875.80 = 398.95/x
  3. Step 3: Cross multiply
    634.79x = 875.80 × 398.95
  4. Step 4: Simplify right side
    634.79x = 349,400.41
  5. Step 5: Solve for x
    x = 349,400.41/634.79
  6. Step 6: Final answer
    x = 550.42

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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.