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Finding the Fourth Proportional to 780.05, 1,170.02 and 455.18

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Solution

The fourth proportional to 780.05, 1,170.02 and 455.18 is: 682.73

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.05 : 1,170.02 = 455.18 : x
  2. Step 2: Convert to fraction form
    780.05/1,170.02 = 455.18/x
  3. Step 3: Cross multiply
    780.05x = 1,170.02 × 455.18
  4. Step 4: Simplify right side
    780.05x = 532,561.58
  5. Step 5: Solve for x
    x = 532,561.58/780.05
  6. Step 6: Final answer
    x = 682.73

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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.