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Finding the Fourth Proportional to 312.85, 471.31 and 286.12

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Solution

The fourth proportional to 312.85, 471.31 and 286.12 is: 431.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    312.85 : 471.31 = 286.12 : x
  2. Step 2: Convert to fraction form
    312.85/471.31 = 286.12/x
  3. Step 3: Cross multiply
    312.85x = 471.31 × 286.12
  4. Step 4: Simplify right side
    312.85x = 134,851.22
  5. Step 5: Solve for x
    x = 134,851.22/312.85
  6. Step 6: Final answer
    x = 431.04

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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.