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Finding the Fourth Proportional to 615.20, 921.30 and 290.66

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Solution

The fourth proportional to 615.20, 921.30 and 290.66 is: 435.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    615.20 : 921.30 = 290.66 : x
  2. Step 2: Convert to fraction form
    615.20/921.30 = 290.66/x
  3. Step 3: Cross multiply
    615.20x = 921.30 × 290.66
  4. Step 4: Simplify right side
    615.20x = 267,785.06
  5. Step 5: Solve for x
    x = 267,785.06/615.20
  6. Step 6: Final answer
    x = 435.28

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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.