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Finding the Fourth Proportional to 421.45, 630.62 and 266.65

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Solution

The fourth proportional to 421.45, 630.62 and 266.65 is: 399.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.45 : 630.62 = 266.65 : x
  2. Step 2: Convert to fraction form
    421.45/630.62 = 266.65/x
  3. Step 3: Cross multiply
    421.45x = 630.62 × 266.65
  4. Step 4: Simplify right side
    421.45x = 168,158.47
  5. Step 5: Solve for x
    x = 168,158.47/421.45
  6. Step 6: Final answer
    x = 399.00

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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.