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Finding the Fourth Proportional to 718.29, 991.19 and 419.49

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Solution

The fourth proportional to 718.29, 991.19 and 419.49 is: 578.87

Step by Step Solution

  1. Step 1: Write the proportion equation
    718.29 : 991.19 = 419.49 : x
  2. Step 2: Convert to fraction form
    718.29/991.19 = 419.49/x
  3. Step 3: Cross multiply
    718.29x = 991.19 × 419.49
  4. Step 4: Simplify right side
    718.29x = 415,795.34
  5. Step 5: Solve for x
    x = 415,795.34/718.29
  6. Step 6: Final answer
    x = 578.87

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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.