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Finding the Fourth Proportional to 870.11, 1,304.25 and 638.65

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Solution

The fourth proportional to 870.11, 1,304.25 and 638.65 is: 957.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    870.11 : 1,304.25 = 638.65 : x
  2. Step 2: Convert to fraction form
    870.11/1,304.25 = 638.65/x
  3. Step 3: Cross multiply
    870.11x = 1,304.25 × 638.65
  4. Step 4: Simplify right side
    870.11x = 832,959.26
  5. Step 5: Solve for x
    x = 832,959.26/870.11
  6. Step 6: Final answer
    x = 957.30

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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.