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Finding the Fourth Proportional to 315.28, 434.80 and 278.48

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Solution

The fourth proportional to 315.28, 434.80 and 278.48 is: 384.05

Step by Step Solution

  1. Step 1: Write the proportion equation
    315.28 : 434.80 = 278.48 : x
  2. Step 2: Convert to fraction form
    315.28/434.80 = 278.48/x
  3. Step 3: Cross multiply
    315.28x = 434.80 × 278.48
  4. Step 4: Simplify right side
    315.28x = 121,083.10
  5. Step 5: Solve for x
    x = 121,083.10/315.28
  6. Step 6: Final answer
    x = 384.05

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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.