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Finding the Fourth Proportional to 719.56, 1,078.84 and 280.80

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Solution

The fourth proportional to 719.56, 1,078.84 and 280.80 is: 421.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    719.56 : 1,078.84 = 280.80 : x
  2. Step 2: Convert to fraction form
    719.56/1,078.84 = 280.80/x
  3. Step 3: Cross multiply
    719.56x = 1,078.84 × 280.80
  4. Step 4: Simplify right side
    719.56x = 302,938.27
  5. Step 5: Solve for x
    x = 302,938.27/719.56
  6. Step 6: Final answer
    x = 421.00

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.