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Finding the Fourth Proportional to 719.00, 991.98 and 420.18

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Solution

The fourth proportional to 719.00, 991.98 and 420.18 is: 579.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    719.00 : 991.98 = 420.18 : x
  2. Step 2: Convert to fraction form
    719.00/991.98 = 420.18/x
  3. Step 3: Cross multiply
    719.00x = 991.98 × 420.18
  4. Step 4: Simplify right side
    719.00x = 416,809.23
  5. Step 5: Solve for x
    x = 416,809.23/719.00
  6. Step 6: Final answer
    x = 579.71

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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.