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Finding the Fourth Proportional to 287.68, 394.08 and 284.80

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Solution

The fourth proportional to 287.68, 394.08 and 284.80 is: 390.13

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.68 : 394.08 = 284.80 : x
  2. Step 2: Convert to fraction form
    287.68/394.08 = 284.80/x
  3. Step 3: Cross multiply
    287.68x = 394.08 × 284.80
  4. Step 4: Simplify right side
    287.68x = 112,233.98
  5. Step 5: Solve for x
    x = 112,233.98/287.68
  6. Step 6: Final answer
    x = 390.13

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Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.