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Finding the Fourth Proportional to 280.80, 421.30 and 98.32

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Solution

The fourth proportional to 280.80, 421.30 and 98.32 is: 147.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    280.80 : 421.30 = 98.32 : x
  2. Step 2: Convert to fraction form
    280.80/421.30 = 98.32/x
  3. Step 3: Cross multiply
    280.80x = 421.30 × 98.32
  4. Step 4: Simplify right side
    280.80x = 41,422.22
  5. Step 5: Solve for x
    x = 41,422.22/280.80
  6. Step 6: Final answer
    x = 147.52

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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.