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Finding the Fourth Proportional to 668.78, 922.80 and 388.88

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Solution

The fourth proportional to 668.78, 922.80 and 388.88 is: 536.59

Step by Step Solution

  1. Step 1: Write the proportion equation
    668.78 : 922.80 = 388.88 : x
  2. Step 2: Convert to fraction form
    668.78/922.80 = 388.88/x
  3. Step 3: Cross multiply
    668.78x = 922.80 × 388.88
  4. Step 4: Simplify right side
    668.78x = 358,858.46
  5. Step 5: Solve for x
    x = 358,858.46/668.78
  6. Step 6: Final answer
    x = 536.59

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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.