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Finding the Fourth Proportional to 862.86, 1,300.09 and 780.69

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Solution

The fourth proportional to 862.86, 1,300.09 and 780.69 is: 1,176.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    862.86 : 1,300.09 = 780.69 : x
  2. Step 2: Convert to fraction form
    862.86/1,300.09 = 780.69/x
  3. Step 3: Cross multiply
    862.86x = 1,300.09 × 780.69
  4. Step 4: Simplify right side
    862.86x = 1,014,967.26
  5. Step 5: Solve for x
    x = 1,014,967.26/862.86
  6. Step 6: Final answer
    x = 1,176.28

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.