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Finding the Fourth Proportional to 388.07, 581.88 and 128.00

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Solution

The fourth proportional to 388.07, 581.88 and 128.00 is: 191.92

Step by Step Solution

  1. Step 1: Write the proportion equation
    388.07 : 581.88 = 128.00 : x
  2. Step 2: Convert to fraction form
    388.07/581.88 = 128.00/x
  3. Step 3: Cross multiply
    388.07x = 581.88 × 128.00
  4. Step 4: Simplify right side
    388.07x = 74,478.58
  5. Step 5: Solve for x
    x = 74,478.58/388.07
  6. Step 6: Final answer
    x = 191.92

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These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.