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Finding the Fourth Proportional to 621.38, 931.34 and 255.72

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Solution

The fourth proportional to 621.38, 931.34 and 255.72 is: 383.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    621.38 : 931.34 = 255.72 : x
  2. Step 2: Convert to fraction form
    621.38/931.34 = 255.72/x
  3. Step 3: Cross multiply
    621.38x = 931.34 × 255.72
  4. Step 4: Simplify right side
    621.38x = 238,160.99
  5. Step 5: Solve for x
    x = 238,160.99/621.38
  6. Step 6: Final answer
    x = 383.28

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1.5x scale

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.