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Finding the Fourth Proportional to 421.12, 630.63 and 266.58

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Solution

The fourth proportional to 421.12, 630.63 and 266.58 is: 399.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.12 : 630.63 = 266.58 : x
  2. Step 2: Convert to fraction form
    421.12/630.63 = 266.58/x
  3. Step 3: Cross multiply
    421.12x = 630.63 × 266.58
  4. Step 4: Simplify right side
    421.12x = 168,108.86
  5. Step 5: Solve for x
    x = 168,108.86/421.12
  6. Step 6: Final answer
    x = 399.20

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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.