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Finding the Fourth Proportional to 1,103.80, 1,662.13 and 815.80

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Solution

The fourth proportional to 1,103.80, 1,662.13 and 815.80 is: 1,228.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,103.80 : 1,662.13 = 815.80 : x
  2. Step 2: Convert to fraction form
    1,103.80/1,662.13 = 815.80/x
  3. Step 3: Cross multiply
    1,103.80x = 1,662.13 × 815.80
  4. Step 4: Simplify right side
    1,103.80x = 1,355,965.65
  5. Step 5: Solve for x
    x = 1,355,965.65/1,103.80
  6. Step 6: Final answer
    x = 1,228.45

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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.