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Finding the Fourth Proportional to 634.98, 877.12 and 478.80

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Solution

The fourth proportional to 634.98, 877.12 and 478.80 is: 661.38

Step by Step Solution

  1. Step 1: Write the proportion equation
    634.98 : 877.12 = 478.80 : x
  2. Step 2: Convert to fraction form
    634.98/877.12 = 478.80/x
  3. Step 3: Cross multiply
    634.98x = 877.12 × 478.80
  4. Step 4: Simplify right side
    634.98x = 419,965.06
  5. Step 5: Solve for x
    x = 419,965.06/634.98
  6. Step 6: Final answer
    x = 661.38

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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.