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Finding the Fourth Proportional to 980.57, 1,353.41 and 649.05

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Solution

The fourth proportional to 980.57, 1,353.41 and 649.05 is: 895.84

Step by Step Solution

  1. Step 1: Write the proportion equation
    980.57 : 1,353.41 = 649.05 : x
  2. Step 2: Convert to fraction form
    980.57/1,353.41 = 649.05/x
  3. Step 3: Cross multiply
    980.57x = 1,353.41 × 649.05
  4. Step 4: Simplify right side
    980.57x = 878,427.52
  5. Step 5: Solve for x
    x = 878,427.52/980.57
  6. Step 6: Final answer
    x = 895.84

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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.