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Finding the Fourth Proportional to 290.79, 438.28 and 278.44

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Solution

The fourth proportional to 290.79, 438.28 and 278.44 is: 419.66

Step by Step Solution

  1. Step 1: Write the proportion equation
    290.79 : 438.28 = 278.44 : x
  2. Step 2: Convert to fraction form
    290.79/438.28 = 278.44/x
  3. Step 3: Cross multiply
    290.79x = 438.28 × 278.44
  4. Step 4: Simplify right side
    290.79x = 122,032.89
  5. Step 5: Solve for x
    x = 122,032.89/290.79
  6. Step 6: Final answer
    x = 419.66

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Why These Related Problems?

These problems maintain the same ratio (1.51) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.