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Finding the Fourth Proportional to 878.40, 1,315.08 and 747.65

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Solution

The fourth proportional to 878.40, 1,315.08 and 747.65 is: 1,119.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    878.40 : 1,315.08 = 747.65 : x
  2. Step 2: Convert to fraction form
    878.40/1,315.08 = 747.65/x
  3. Step 3: Cross multiply
    878.40x = 1,315.08 × 747.65
  4. Step 4: Simplify right side
    878.40x = 983,212.99
  5. Step 5: Solve for x
    x = 983,212.99/878.40
  6. Step 6: Final answer
    x = 1,119.32

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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.