Home / 3,138.72-4,707.75-1,905.78

Finding the Fourth Proportional to 3,138.72, 4,707.75 and 1,905.78

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Solution

The fourth proportional to 3,138.72, 4,707.75 and 1,905.78 is: 2,858.47

Step by Step Solution

  1. Step 1: Write the proportion equation
    3,138.72 : 4,707.75 = 1,905.78 : x
  2. Step 2: Convert to fraction form
    3,138.72/4,707.75 = 1,905.78/x
  3. Step 3: Cross multiply
    3,138.72x = 4,707.75 × 1,905.78
  4. Step 4: Simplify right side
    3,138.72x = 8,971,935.80
  5. Step 5: Solve for x
    x = 8,971,935.80/3,138.72
  6. Step 6: Final answer
    x = 2,858.47

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1.5x scale

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.