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Finding the Fourth Proportional to 615.39, 921.71 and 354.78

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Solution

The fourth proportional to 615.39, 921.71 and 354.78 is: 531.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    615.39 : 921.71 = 354.78 : x
  2. Step 2: Convert to fraction form
    615.39/921.71 = 354.78/x
  3. Step 3: Cross multiply
    615.39x = 921.71 × 354.78
  4. Step 4: Simplify right side
    615.39x = 327,002.50
  5. Step 5: Solve for x
    x = 327,002.50/615.39
  6. Step 6: Final answer
    x = 531.37

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1.5x scale

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.