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Finding the Fourth Proportional to 620.78, 931.02 and 255.50

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Solution

The fourth proportional to 620.78, 931.02 and 255.50 is: 383.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.78 : 931.02 = 255.50 : x
  2. Step 2: Convert to fraction form
    620.78/931.02 = 255.50/x
  3. Step 3: Cross multiply
    620.78x = 931.02 × 255.50
  4. Step 4: Simplify right side
    620.78x = 237,875.61
  5. Step 5: Solve for x
    x = 237,875.61/620.78
  6. Step 6: Final answer
    x = 383.19

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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.