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Finding the Fourth Proportional to 147.39, 221.08 and 66.21

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Solution

The fourth proportional to 147.39, 221.08 and 66.21 is: 99.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    147.39 : 221.08 = 66.21 : x
  2. Step 2: Convert to fraction form
    147.39/221.08 = 66.21/x
  3. Step 3: Cross multiply
    147.39x = 221.08 × 66.21
  4. Step 4: Simplify right side
    147.39x = 14,637.71
  5. Step 5: Solve for x
    x = 14,637.71/147.39
  6. Step 6: Final answer
    x = 99.31

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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.