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Finding the Fourth Proportional to 410.81, 615.74 and 256.79

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Solution

The fourth proportional to 410.81, 615.74 and 256.79 is: 384.89

Step by Step Solution

  1. Step 1: Write the proportion equation
    410.81 : 615.74 = 256.79 : x
  2. Step 2: Convert to fraction form
    410.81/615.74 = 256.79/x
  3. Step 3: Cross multiply
    410.81x = 615.74 × 256.79
  4. Step 4: Simplify right side
    410.81x = 158,116.13
  5. Step 5: Solve for x
    x = 158,116.13/410.81
  6. Step 6: Final answer
    x = 384.89

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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.