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Finding the Fourth Proportional to 818.96, 1,228.08 and 780.80

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Solution

The fourth proportional to 818.96, 1,228.08 and 780.80 is: 1,170.86

Step by Step Solution

  1. Step 1: Write the proportion equation
    818.96 : 1,228.08 = 780.80 : x
  2. Step 2: Convert to fraction form
    818.96/1,228.08 = 780.80/x
  3. Step 3: Cross multiply
    818.96x = 1,228.08 × 780.80
  4. Step 4: Simplify right side
    818.96x = 958,884.86
  5. Step 5: Solve for x
    x = 958,884.86/818.96
  6. Step 6: Final answer
    x = 1,170.86

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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.