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Finding the Fourth Proportional to 780.28, 1,170 and 487.06

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Solution

The fourth proportional to 780.28, 1,170 and 487.06 is: 730.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.28 : 1,170 = 487.06 : x
  2. Step 2: Convert to fraction form
    780.28/1,170 = 487.06/x
  3. Step 3: Cross multiply
    780.28x = 1,170 × 487.06
  4. Step 4: Simplify right side
    780.28x = 569,860.20
  5. Step 5: Solve for x
    x = 569,860.20/780.28
  6. Step 6: Final answer
    x = 730.33

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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.