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Finding the Fourth Proportional to 668.08, 921.84 and 388.39

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Solution

The fourth proportional to 668.08, 921.84 and 388.39 is: 535.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    668.08 : 921.84 = 388.39 : x
  2. Step 2: Convert to fraction form
    668.08/921.84 = 388.39/x
  3. Step 3: Cross multiply
    668.08x = 921.84 × 388.39
  4. Step 4: Simplify right side
    668.08x = 358,033.44
  5. Step 5: Solve for x
    x = 358,033.44/668.08
  6. Step 6: Final answer
    x = 535.91

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1.5x scale

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.