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Finding the Fourth Proportional to 618.95, 854.13 and 386.21

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Solution

The fourth proportional to 618.95, 854.13 and 386.21 is: 532.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    618.95 : 854.13 = 386.21 : x
  2. Step 2: Convert to fraction form
    618.95/854.13 = 386.21/x
  3. Step 3: Cross multiply
    618.95x = 854.13 × 386.21
  4. Step 4: Simplify right side
    618.95x = 329,869.28
  5. Step 5: Solve for x
    x = 329,869.28/618.95
  6. Step 6: Final answer
    x = 532.95

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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.