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Finding the Fourth Proportional to 421.65, 632.28 and 129.06

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Solution

The fourth proportional to 421.65, 632.28 and 129.06 is: 193.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.65 : 632.28 = 129.06 : x
  2. Step 2: Convert to fraction form
    421.65/632.28 = 129.06/x
  3. Step 3: Cross multiply
    421.65x = 632.28 × 129.06
  4. Step 4: Simplify right side
    421.65x = 81,602.06
  5. Step 5: Solve for x
    x = 81,602.06/421.65
  6. Step 6: Final answer
    x = 193.53

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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.