Home / 1,912.76-2,638.78-1,387.88

Finding the Fourth Proportional to 1,912.76, 2,638.78 and 1,387.88

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Solution

The fourth proportional to 1,912.76, 2,638.78 and 1,387.88 is: 1,914.67

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,912.76 : 2,638.78 = 1,387.88 : x
  2. Step 2: Convert to fraction form
    1,912.76/2,638.78 = 1,387.88/x
  3. Step 3: Cross multiply
    1,912.76x = 2,638.78 × 1,387.88
  4. Step 4: Simplify right side
    1,912.76x = 3,662,309.99
  5. Step 5: Solve for x
    x = 3,662,309.99/1,912.76
  6. Step 6: Final answer
    x = 1,914.67

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1.5x scale

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.