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Finding the Fourth Proportional to 777.20, 1,160.10 and 680

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Solution

The fourth proportional to 777.20, 1,160.10 and 680 is: 1,015.01

Step by Step Solution

  1. Step 1: Write the proportion equation
    777.20 : 1,160.10 = 680 : x
  2. Step 2: Convert to fraction form
    777.20/1,160.10 = 680/x
  3. Step 3: Cross multiply
    777.20x = 1,160.10 × 680
  4. Step 4: Simplify right side
    777.20x = 788,868.00
  5. Step 5: Solve for x
    x = 788,868.00/777.20
  6. Step 6: Final answer
    x = 1,015.01

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.