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Finding the Fourth Proportional to 699.28, 964.98 and 388.80

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Solution

The fourth proportional to 699.28, 964.98 and 388.80 is: 536.53

Step by Step Solution

  1. Step 1: Write the proportion equation
    699.28 : 964.98 = 388.80 : x
  2. Step 2: Convert to fraction form
    699.28/964.98 = 388.80/x
  3. Step 3: Cross multiply
    699.28x = 964.98 × 388.80
  4. Step 4: Simplify right side
    699.28x = 375,184.22
  5. Step 5: Solve for x
    x = 375,184.22/699.28
  6. Step 6: Final answer
    x = 536.53

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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.