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Finding the Fourth Proportional to 980.71, 1,352.65 and 630.79

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Solution

The fourth proportional to 980.71, 1,352.65 and 630.79 is: 870.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    980.71 : 1,352.65 = 630.79 : x
  2. Step 2: Convert to fraction form
    980.71/1,352.65 = 630.79/x
  3. Step 3: Cross multiply
    980.71x = 1,352.65 × 630.79
  4. Step 4: Simplify right side
    980.71x = 853,238.09
  5. Step 5: Solve for x
    x = 853,238.09/980.71
  6. Step 6: Final answer
    x = 870.02

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.