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Finding the Fourth Proportional to 870.34, 1,305.50 and 221.08

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Solution

The fourth proportional to 870.34, 1,305.50 and 221.08 is: 331.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    870.34 : 1,305.50 = 221.08 : x
  2. Step 2: Convert to fraction form
    870.34/1,305.50 = 221.08/x
  3. Step 3: Cross multiply
    870.34x = 1,305.50 × 221.08
  4. Step 4: Simplify right side
    870.34x = 288,619.94
  5. Step 5: Solve for x
    x = 288,619.94/870.34
  6. Step 6: Final answer
    x = 331.62

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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.