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Finding the Fourth Proportional to 410.40, 615.60 and 257.30

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Solution

The fourth proportional to 410.40, 615.60 and 257.30 is: 385.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    410.40 : 615.60 = 257.30 : x
  2. Step 2: Convert to fraction form
    410.40/615.60 = 257.30/x
  3. Step 3: Cross multiply
    410.40x = 615.60 × 257.30
  4. Step 4: Simplify right side
    410.40x = 158,393.88
  5. Step 5: Solve for x
    x = 158,393.88/410.40
  6. Step 6: Final answer
    x = 385.95

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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.