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Finding the Fourth Proportional to 660.25, 990.38 and 275.50

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Solution

The fourth proportional to 660.25, 990.38 and 275.50 is: 413.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    660.25 : 990.38 = 275.50 : x
  2. Step 2: Convert to fraction form
    660.25/990.38 = 275.50/x
  3. Step 3: Cross multiply
    660.25x = 990.38 × 275.50
  4. Step 4: Simplify right side
    660.25x = 272,849.69
  5. Step 5: Solve for x
    x = 272,849.69/660.25
  6. Step 6: Final answer
    x = 413.25

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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.