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Finding the Fourth Proportional to 486.72, 671.44 and 312

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Solution

The fourth proportional to 486.72, 671.44 and 312 is: 430.41

Step by Step Solution

  1. Step 1: Write the proportion equation
    486.72 : 671.44 = 312 : x
  2. Step 2: Convert to fraction form
    486.72/671.44 = 312/x
  3. Step 3: Cross multiply
    486.72x = 671.44 × 312
  4. Step 4: Simplify right side
    486.72x = 209,489.28
  5. Step 5: Solve for x
    x = 209,489.28/486.72
  6. Step 6: Final answer
    x = 430.41

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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.