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Finding the Fourth Proportional to 784.40, 1,081.32 and 521.96

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Solution

The fourth proportional to 784.40, 1,081.32 and 521.96 is: 719.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    784.40 : 1,081.32 = 521.96 : x
  2. Step 2: Convert to fraction form
    784.40/1,081.32 = 521.96/x
  3. Step 3: Cross multiply
    784.40x = 1,081.32 × 521.96
  4. Step 4: Simplify right side
    784.40x = 564,405.79
  5. Step 5: Solve for x
    x = 564,405.79/784.40
  6. Step 6: Final answer
    x = 719.54

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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.