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Finding the Fourth Proportional to 410.21, 615.15 and 256.21

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Solution

The fourth proportional to 410.21, 615.15 and 256.21 is: 384.21

Step by Step Solution

  1. Step 1: Write the proportion equation
    410.21 : 615.15 = 256.21 : x
  2. Step 2: Convert to fraction form
    410.21/615.15 = 256.21/x
  3. Step 3: Cross multiply
    410.21x = 615.15 × 256.21
  4. Step 4: Simplify right side
    410.21x = 157,607.58
  5. Step 5: Solve for x
    x = 157,607.58/410.21
  6. Step 6: Final answer
    x = 384.21

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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.