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Finding the Fourth Proportional to 870.41, 1,305.65 and 221.15

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Solution

The fourth proportional to 870.41, 1,305.65 and 221.15 is: 331.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    870.41 : 1,305.65 = 221.15 : x
  2. Step 2: Convert to fraction form
    870.41/1,305.65 = 221.15/x
  3. Step 3: Cross multiply
    870.41x = 1,305.65 × 221.15
  4. Step 4: Simplify right side
    870.41x = 288,744.50
  5. Step 5: Solve for x
    x = 288,744.50/870.41
  6. Step 6: Final answer
    x = 331.73

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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.