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Finding the Fourth Proportional to 298.80, 412.40 and 274.20

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Solution

The fourth proportional to 298.80, 412.40 and 274.20 is: 378.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    298.80 : 412.40 = 274.20 : x
  2. Step 2: Convert to fraction form
    298.80/412.40 = 274.20/x
  3. Step 3: Cross multiply
    298.80x = 412.40 × 274.20
  4. Step 4: Simplify right side
    298.80x = 113,080.08
  5. Step 5: Solve for x
    x = 113,080.08/298.80
  6. Step 6: Final answer
    x = 378.45

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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.