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Finding the Fourth Proportional to 719.62, 991.79 and 619.78

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Solution

The fourth proportional to 719.62, 991.79 and 619.78 is: 854.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    719.62 : 991.79 = 619.78 : x
  2. Step 2: Convert to fraction form
    719.62/991.79 = 619.78/x
  3. Step 3: Cross multiply
    719.62x = 991.79 × 619.78
  4. Step 4: Simplify right side
    719.62x = 614,686.65
  5. Step 5: Solve for x
    x = 614,686.65/719.62
  6. Step 6: Final answer
    x = 854.19

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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.