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Finding the Fourth Proportional to 319.18, 478.72 and 145.81

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Solution

The fourth proportional to 319.18, 478.72 and 145.81 is: 218.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    319.18 : 478.72 = 145.81 : x
  2. Step 2: Convert to fraction form
    319.18/478.72 = 145.81/x
  3. Step 3: Cross multiply
    319.18x = 478.72 × 145.81
  4. Step 4: Simplify right side
    319.18x = 69,801.19
  5. Step 5: Solve for x
    x = 69,801.19/319.18
  6. Step 6: Final answer
    x = 218.69

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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.