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Finding the Fourth Proportional to 699.28, 965.01 and 388.78

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Solution

The fourth proportional to 699.28, 965.01 and 388.78 is: 536.52

Step by Step Solution

  1. Step 1: Write the proportion equation
    699.28 : 965.01 = 388.78 : x
  2. Step 2: Convert to fraction form
    699.28/965.01 = 388.78/x
  3. Step 3: Cross multiply
    699.28x = 965.01 × 388.78
  4. Step 4: Simplify right side
    699.28x = 375,176.59
  5. Step 5: Solve for x
    x = 375,176.59/699.28
  6. Step 6: Final answer
    x = 536.52

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.