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Finding the Fourth Proportional to 287.88, 431.40 and 219.18

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Solution

The fourth proportional to 287.88, 431.40 and 219.18 is: 328.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    287.88 : 431.40 = 219.18 : x
  2. Step 2: Convert to fraction form
    287.88/431.40 = 219.18/x
  3. Step 3: Cross multiply
    287.88x = 431.40 × 219.18
  4. Step 4: Simplify right side
    287.88x = 94,554.25
  5. Step 5: Solve for x
    x = 94,554.25/287.88
  6. Step 6: Final answer
    x = 328.45

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Why These Related Problems?

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