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Finding the Fourth Proportional to 1,308.80, 1,806.24 and 785.12

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Solution

The fourth proportional to 1,308.80, 1,806.24 and 785.12 is: 1,083.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,308.80 : 1,806.24 = 785.12 : x
  2. Step 2: Convert to fraction form
    1,308.80/1,806.24 = 785.12/x
  3. Step 3: Cross multiply
    1,308.80x = 1,806.24 × 785.12
  4. Step 4: Simplify right side
    1,308.80x = 1,418,115.15
  5. Step 5: Solve for x
    x = 1,418,115.15/1,308.80
  6. Step 6: Final answer
    x = 1,083.52

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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.