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Finding the Fourth Proportional to 980.05, 1,352.54 and 647.90

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Solution

The fourth proportional to 980.05, 1,352.54 and 647.90 is: 894.15

Step by Step Solution

  1. Step 1: Write the proportion equation
    980.05 : 1,352.54 = 647.90 : x
  2. Step 2: Convert to fraction form
    980.05/1,352.54 = 647.90/x
  3. Step 3: Cross multiply
    980.05x = 1,352.54 × 647.90
  4. Step 4: Simplify right side
    980.05x = 876,310.67
  5. Step 5: Solve for x
    x = 876,310.67/980.05
  6. Step 6: Final answer
    x = 894.15

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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.