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Finding the Fourth Proportional to 780.48, 1,170.92 and 649.77

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Solution

The fourth proportional to 780.48, 1,170.92 and 649.77 is: 974.82

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.48 : 1,170.92 = 649.77 : x
  2. Step 2: Convert to fraction form
    780.48/1,170.92 = 649.77/x
  3. Step 3: Cross multiply
    780.48x = 1,170.92 × 649.77
  4. Step 4: Simplify right side
    780.48x = 760,828.69
  5. Step 5: Solve for x
    x = 760,828.69/780.48
  6. Step 6: Final answer
    x = 974.82

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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.