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Finding the Fourth Proportional to 778.50, 1,075.26 and 631.89

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Solution

The fourth proportional to 778.50, 1,075.26 and 631.89 is: 872.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    778.50 : 1,075.26 = 631.89 : x
  2. Step 2: Convert to fraction form
    778.50/1,075.26 = 631.89/x
  3. Step 3: Cross multiply
    778.50x = 1,075.26 × 631.89
  4. Step 4: Simplify right side
    778.50x = 679,446.04
  5. Step 5: Solve for x
    x = 679,446.04/778.50
  6. Step 6: Final answer
    x = 872.76

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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.