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Finding the Fourth Proportional to 668.19, 921.93 and 388.41

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Solution

The fourth proportional to 668.19, 921.93 and 388.41 is: 535.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    668.19 : 921.93 = 388.41 : x
  2. Step 2: Convert to fraction form
    668.19/921.93 = 388.41/x
  3. Step 3: Cross multiply
    668.19x = 921.93 × 388.41
  4. Step 4: Simplify right side
    668.19x = 358,086.83
  5. Step 5: Solve for x
    x = 358,086.83/668.19
  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.