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Finding the Fourth Proportional to 869.05, 1,200.86 and 619.93

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Solution

The fourth proportional to 869.05, 1,200.86 and 619.93 is: 856.62

Step by Step Solution

  1. Step 1: Write the proportion equation
    869.05 : 1,200.86 = 619.93 : x
  2. Step 2: Convert to fraction form
    869.05/1,200.86 = 619.93/x
  3. Step 3: Cross multiply
    869.05x = 1,200.86 × 619.93
  4. Step 4: Simplify right side
    869.05x = 744,449.14
  5. Step 5: Solve for x
    x = 744,449.14/869.05
  6. Step 6: Final answer
    x = 856.62

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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.