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Finding the Fourth Proportional to 371.07, 556.21 and 139.81

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Solution

The fourth proportional to 371.07, 556.21 and 139.81 is: 209.57

Step by Step Solution

  1. Step 1: Write the proportion equation
    371.07 : 556.21 = 139.81 : x
  2. Step 2: Convert to fraction form
    371.07/556.21 = 139.81/x
  3. Step 3: Cross multiply
    371.07x = 556.21 × 139.81
  4. Step 4: Simplify right side
    371.07x = 77,763.72
  5. Step 5: Solve for x
    x = 77,763.72/371.07
  6. Step 6: Final answer
    x = 209.57

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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.