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Finding the Fourth Proportional to 378.79, 521.87 and 247.57

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Solution

The fourth proportional to 378.79, 521.87 and 247.57 is: 341.08

Step by Step Solution

  1. Step 1: Write the proportion equation
    378.79 : 521.87 = 247.57 : x
  2. Step 2: Convert to fraction form
    378.79/521.87 = 247.57/x
  3. Step 3: Cross multiply
    378.79x = 521.87 × 247.57
  4. Step 4: Simplify right side
    378.79x = 129,195.51
  5. Step 5: Solve for x
    x = 129,195.51/378.79
  6. Step 6: Final answer
    x = 341.08

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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.