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Finding the Fourth Proportional to 634.77, 875.61 and 398.79

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Solution

The fourth proportional to 634.77, 875.61 and 398.79 is: 550.10

Step by Step Solution

  1. Step 1: Write the proportion equation
    634.77 : 875.61 = 398.79 : x
  2. Step 2: Convert to fraction form
    634.77/875.61 = 398.79/x
  3. Step 3: Cross multiply
    634.77x = 875.61 × 398.79
  4. Step 4: Simplify right side
    634.77x = 349,184.51
  5. Step 5: Solve for x
    x = 349,184.51/634.77
  6. Step 6: Final answer
    x = 550.10

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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.