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Finding the Fourth Proportional to 780.06, 1,170.09 and 455.20

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Solution

The fourth proportional to 780.06, 1,170.09 and 455.20 is: 682.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.06 : 1,170.09 = 455.20 : x
  2. Step 2: Convert to fraction form
    780.06/1,170.09 = 455.20/x
  3. Step 3: Cross multiply
    780.06x = 1,170.09 × 455.20
  4. Step 4: Simplify right side
    780.06x = 532,624.97
  5. Step 5: Solve for x
    x = 532,624.97/780.06
  6. Step 6: Final answer
    x = 682.80

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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.