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Finding the Fourth Proportional to 870.82, 1,305.26 and 628.40

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Solution

The fourth proportional to 870.82, 1,305.26 and 628.40 is: 941.90

Step by Step Solution

  1. Step 1: Write the proportion equation
    870.82 : 1,305.26 = 628.40 : x
  2. Step 2: Convert to fraction form
    870.82/1,305.26 = 628.40/x
  3. Step 3: Cross multiply
    870.82x = 1,305.26 × 628.40
  4. Step 4: Simplify right side
    870.82x = 820,225.38
  5. Step 5: Solve for x
    x = 820,225.38/870.82
  6. Step 6: Final answer
    x = 941.90

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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.