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Finding the Fourth Proportional to 661.71, 991.95 and 251.10

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Solution

The fourth proportional to 661.71, 991.95 and 251.10 is: 376.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    661.71 : 991.95 = 251.10 : x
  2. Step 2: Convert to fraction form
    661.71/991.95 = 251.10/x
  3. Step 3: Cross multiply
    661.71x = 991.95 × 251.10
  4. Step 4: Simplify right side
    661.71x = 249,078.65
  5. Step 5: Solve for x
    x = 249,078.65/661.71
  6. Step 6: Final answer
    x = 376.42

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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.