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Finding the Fourth Proportional to 615.10, 922.65 and 420.70

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Solution

The fourth proportional to 615.10, 922.65 and 420.70 is: 631.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    615.10 : 922.65 = 420.70 : x
  2. Step 2: Convert to fraction form
    615.10/922.65 = 420.70/x
  3. Step 3: Cross multiply
    615.10x = 922.65 × 420.70
  4. Step 4: Simplify right side
    615.10x = 388,158.86
  5. Step 5: Solve for x
    x = 388,158.86/615.10
  6. Step 6: Final answer
    x = 631.05

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Similar ratio
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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.