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Finding the Fourth Proportional to 857.64, 1,288.20 and 757.20

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Solution

The fourth proportional to 857.64, 1,288.20 and 757.20 is: 1,137.34

Step by Step Solution

  1. Step 1: Write the proportion equation
    857.64 : 1,288.20 = 757.20 : x
  2. Step 2: Convert to fraction form
    857.64/1,288.20 = 757.20/x
  3. Step 3: Cross multiply
    857.64x = 1,288.20 × 757.20
  4. Step 4: Simplify right side
    857.64x = 975,425.04
  5. Step 5: Solve for x
    x = 975,425.04/857.64
  6. Step 6: Final answer
    x = 1,137.34

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.