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Finding the Fourth Proportional to 807.91, 1,114.16 and 642.67

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Solution

The fourth proportional to 807.91, 1,114.16 and 642.67 is: 886.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    807.91 : 1,114.16 = 642.67 : x
  2. Step 2: Convert to fraction form
    807.91/1,114.16 = 642.67/x
  3. Step 3: Cross multiply
    807.91x = 1,114.16 × 642.67
  4. Step 4: Simplify right side
    807.91x = 716,031.21
  5. Step 5: Solve for x
    x = 716,031.21/807.91
  6. Step 6: Final answer
    x = 886.28

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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.