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Finding the Fourth Proportional to 287.66, 398.86 and 277.40

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Solution

The fourth proportional to 287.66, 398.86 and 277.40 is: 384.63

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.66 : 398.86 = 277.40 : x
  2. Step 2: Convert to fraction form
    287.66/398.86 = 277.40/x
  3. Step 3: Cross multiply
    287.66x = 398.86 × 277.40
  4. Step 4: Simplify right side
    287.66x = 110,643.76
  5. Step 5: Solve for x
    x = 110,643.76/287.66
  6. Step 6: Final answer
    x = 384.63

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Why These Related Problems?

These problems maintain the same ratio (1.39) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.