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Finding the Fourth Proportional to 905.31, 1,250.24 and 780.28

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Solution

The fourth proportional to 905.31, 1,250.24 and 780.28 is: 1,077.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    905.31 : 1,250.24 = 780.28 : x
  2. Step 2: Convert to fraction form
    905.31/1,250.24 = 780.28/x
  3. Step 3: Cross multiply
    905.31x = 1,250.24 × 780.28
  4. Step 4: Simplify right side
    905.31x = 975,530.24
  5. Step 5: Solve for x
    x = 975,530.24/905.31
  6. Step 6: Final answer
    x = 1,077.56

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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.