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Finding the Fourth Proportional to 278.80, 417.60 and 248.40

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Solution

The fourth proportional to 278.80, 417.60 and 248.40 is: 372.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    278.80 : 417.60 = 248.40 : x
  2. Step 2: Convert to fraction form
    278.80/417.60 = 248.40/x
  3. Step 3: Cross multiply
    278.80x = 417.60 × 248.40
  4. Step 4: Simplify right side
    278.80x = 103,731.84
  5. Step 5: Solve for x
    x = 103,731.84/278.80
  6. Step 6: Final answer
    x = 372.07

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Why These Related Problems?

These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.