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Finding the Fourth Proportional to 680, 940 and 619.28

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Solution

The fourth proportional to 680, 940 and 619.28 is: 856.06

Step by Step Solution

  1. Step 1: Write the proportion equation
    680 : 940 = 619.28 : x
  2. Step 2: Convert to fraction form
    680/940 = 619.28/x
  3. Step 3: Cross multiply
    680x = 940 × 619.28
  4. Step 4: Simplify right side
    680x = 582,123.20
  5. Step 5: Solve for x
    x = 582,123.20/680
  6. Step 6: Final answer
    x = 856.06

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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.