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Finding the Fourth Proportional to 421.40, 632.10 and 306.20

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Solution

The fourth proportional to 421.40, 632.10 and 306.20 is: 459.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.40 : 632.10 = 306.20 : x
  2. Step 2: Convert to fraction form
    421.40/632.10 = 306.20/x
  3. Step 3: Cross multiply
    421.40x = 632.10 × 306.20
  4. Step 4: Simplify right side
    421.40x = 193,549.02
  5. Step 5: Solve for x
    x = 193,549.02/421.40
  6. Step 6: Final answer
    x = 459.30

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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.