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Finding the Fourth Proportional to 777.80, 1,074.91 and 637.70

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Solution

The fourth proportional to 777.80, 1,074.91 and 637.70 is: 881.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    777.80 : 1,074.91 = 637.70 : x
  2. Step 2: Convert to fraction form
    777.80/1,074.91 = 637.70/x
  3. Step 3: Cross multiply
    777.80x = 1,074.91 × 637.70
  4. Step 4: Simplify right side
    777.80x = 685,466.92
  5. Step 5: Solve for x
    x = 685,466.92/777.80
  6. Step 6: Final answer
    x = 881.30

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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.