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Finding the Fourth Proportional to 869.02, 1,200.81 and 619.91

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Solution

The fourth proportional to 869.02, 1,200.81 and 619.91 is: 856.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    869.02 : 1,200.81 = 619.91 : x
  2. Step 2: Convert to fraction form
    869.02/1,200.81 = 619.91/x
  3. Step 3: Cross multiply
    869.02x = 1,200.81 × 619.91
  4. Step 4: Simplify right side
    869.02x = 744,394.13
  5. Step 5: Solve for x
    x = 744,394.13/869.02
  6. Step 6: Final answer
    x = 856.59

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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.