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Finding the Fourth Proportional to 780.33, 1,170.10 and 260.15

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Solution

The fourth proportional to 780.33, 1,170.10 and 260.15 is: 390.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    780.33 : 1,170.10 = 260.15 : x
  2. Step 2: Convert to fraction form
    780.33/1,170.10 = 260.15/x
  3. Step 3: Cross multiply
    780.33x = 1,170.10 × 260.15
  4. Step 4: Simplify right side
    780.33x = 304,400.13
  5. Step 5: Solve for x
    x = 304,400.13/780.33
  6. Step 6: Final answer
    x = 390.09

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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.