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Finding the Fourth Proportional to 980.88, 1,353.04 and 649.20

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Solution

The fourth proportional to 980.88, 1,353.04 and 649.20 is: 895.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    980.88 : 1,353.04 = 649.20 : x
  2. Step 2: Convert to fraction form
    980.88/1,353.04 = 649.20/x
  3. Step 3: Cross multiply
    980.88x = 1,353.04 × 649.20
  4. Step 4: Simplify right side
    980.88x = 878,393.57
  5. Step 5: Solve for x
    x = 878,393.57/980.88
  6. Step 6: Final answer
    x = 895.52

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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.