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Finding the Fourth Proportional to 668.17, 921.99 and 388.47

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Solution

The fourth proportional to 668.17, 921.99 and 388.47 is: 536.04

Step by Step Solution

  1. Step 1: Write the proportion equation
    668.17 : 921.99 = 388.47 : x
  2. Step 2: Convert to fraction form
    668.17/921.99 = 388.47/x
  3. Step 3: Cross multiply
    668.17x = 921.99 × 388.47
  4. Step 4: Simplify right side
    668.17x = 358,165.46
  5. Step 5: Solve for x
    x = 358,165.46/668.17
  6. Step 6: Final answer
    x = 536.04

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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.