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Finding the Fourth Proportional to 621.19, 931.17 and 256.28

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Solution

The fourth proportional to 621.19, 931.17 and 256.28 is: 384.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    621.19 : 931.17 = 256.28 : x
  2. Step 2: Convert to fraction form
    621.19/931.17 = 256.28/x
  3. Step 3: Cross multiply
    621.19x = 931.17 × 256.28
  4. Step 4: Simplify right side
    621.19x = 238,642.58
  5. Step 5: Solve for x
    x = 238,642.58/621.19
  6. Step 6: Final answer
    x = 384.17

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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.