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Finding the Fourth Proportional to 421.30, 631.52 and 147.30

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Solution

The fourth proportional to 421.30, 631.52 and 147.30 is: 220.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.30 : 631.52 = 147.30 : x
  2. Step 2: Convert to fraction form
    421.30/631.52 = 147.30/x
  3. Step 3: Cross multiply
    421.30x = 631.52 × 147.30
  4. Step 4: Simplify right side
    421.30x = 93,022.90
  5. Step 5: Solve for x
    x = 93,022.90/421.30
  6. Step 6: Final answer
    x = 220.80

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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.