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Finding the Fourth Proportional to 869.70, 1,199.64 and 648.87

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Solution

The fourth proportional to 869.70, 1,199.64 and 648.87 is: 895.03

Step by Step Solution

  1. Step 1: Write the proportion equation
    869.70 : 1,199.64 = 648.87 : x
  2. Step 2: Convert to fraction form
    869.70/1,199.64 = 648.87/x
  3. Step 3: Cross multiply
    869.70x = 1,199.64 × 648.87
  4. Step 4: Simplify right side
    869.70x = 778,410.41
  5. Step 5: Solve for x
    x = 778,410.41/869.70
  6. Step 6: Final answer
    x = 895.03

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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.