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Finding the Fourth Proportional to 784.42, 1,081.85 and 660.38

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Solution

The fourth proportional to 784.42, 1,081.85 and 660.38 is: 910.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    784.42 : 1,081.85 = 660.38 : x
  2. Step 2: Convert to fraction form
    784.42/1,081.85 = 660.38/x
  3. Step 3: Cross multiply
    784.42x = 1,081.85 × 660.38
  4. Step 4: Simplify right side
    784.42x = 714,423.39
  5. Step 5: Solve for x
    x = 714,423.39/784.42
  6. Step 6: Final answer
    x = 910.77

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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.