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Finding the Fourth Proportional to 788.50, 1,089.66 and 648.39

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Solution

The fourth proportional to 788.50, 1,089.66 and 648.39 is: 896.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    788.50 : 1,089.66 = 648.39 : x
  2. Step 2: Convert to fraction form
    788.50/1,089.66 = 648.39/x
  3. Step 3: Cross multiply
    788.50x = 1,089.66 × 648.39
  4. Step 4: Simplify right side
    788.50x = 706,524.65
  5. Step 5: Solve for x
    x = 706,524.65/788.50
  6. Step 6: Final answer
    x = 896.04

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.