Home / 1,638.42-2,261.04-939.78

Finding the Fourth Proportional to 1,638.42, 2,261.04 and 939.78

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Solution

The fourth proportional to 1,638.42, 2,261.04 and 939.78 is: 1,296.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,638.42 : 2,261.04 = 939.78 : x
  2. Step 2: Convert to fraction form
    1,638.42/2,261.04 = 939.78/x
  3. Step 3: Cross multiply
    1,638.42x = 2,261.04 × 939.78
  4. Step 4: Simplify right side
    1,638.42x = 2,124,880.17
  5. Step 5: Solve for x
    x = 2,124,880.17/1,638.42
  6. Step 6: Final answer
    x = 1,296.91

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.