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Finding the Fourth Proportional to 421.03, 630.55 and 215.08

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Solution

The fourth proportional to 421.03, 630.55 and 215.08 is: 322.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    421.03 : 630.55 = 215.08 : x
  2. Step 2: Convert to fraction form
    421.03/630.55 = 215.08/x
  3. Step 3: Cross multiply
    421.03x = 630.55 × 215.08
  4. Step 4: Simplify right side
    421.03x = 135,618.69
  5. Step 5: Solve for x
    x = 135,618.69/421.03
  6. Step 6: Final answer
    x = 322.11

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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.