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Finding the Fourth Proportional to 620.69, 931.39 and 278.69

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Solution

The fourth proportional to 620.69, 931.39 and 278.69 is: 418.19

Step by Step Solution

  1. Step 1: Write the proportion equation
    620.69 : 931.39 = 278.69 : x
  2. Step 2: Convert to fraction form
    620.69/931.39 = 278.69/x
  3. Step 3: Cross multiply
    620.69x = 931.39 × 278.69
  4. Step 4: Simplify right side
    620.69x = 259,569.08
  5. Step 5: Solve for x
    x = 259,569.08/620.69
  6. Step 6: Final answer
    x = 418.19

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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.