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Finding the Fourth Proportional to 653.50, 980.40 and 268.78

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Solution

The fourth proportional to 653.50, 980.40 and 268.78 is: 403.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    653.50 : 980.40 = 268.78 : x
  2. Step 2: Convert to fraction form
    653.50/980.40 = 268.78/x
  3. Step 3: Cross multiply
    653.50x = 980.40 × 268.78
  4. Step 4: Simplify right side
    653.50x = 263,511.91
  5. Step 5: Solve for x
    x = 263,511.91/653.50
  6. Step 6: Final answer
    x = 403.23

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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.