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Finding the Fourth Proportional to 319.02, 478.55 and 99.71

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Solution

The fourth proportional to 319.02, 478.55 and 99.71 is: 149.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    319.02 : 478.55 = 99.71 : x
  2. Step 2: Convert to fraction form
    319.02/478.55 = 99.71/x
  3. Step 3: Cross multiply
    319.02x = 478.55 × 99.71
  4. Step 4: Simplify right side
    319.02x = 47,713.33
  5. Step 5: Solve for x
    x = 47,713.33/319.02
  6. Step 6: Final answer
    x = 149.56

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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.