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Finding the Fourth Proportional to 615.39, 922.41 and 420.45

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Solution

The fourth proportional to 615.39, 922.41 and 420.45 is: 630.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    615.39 : 922.41 = 420.45 : x
  2. Step 2: Convert to fraction form
    615.39/922.41 = 420.45/x
  3. Step 3: Cross multiply
    615.39x = 922.41 × 420.45
  4. Step 4: Simplify right side
    615.39x = 387,827.28
  5. Step 5: Solve for x
    x = 387,827.28/615.39
  6. Step 6: Final answer
    x = 630.21

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.