Home / 1,638.28-2,457.56-815.72

Finding the Fourth Proportional to 1,638.28, 2,457.56 and 815.72

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Solution

The fourth proportional to 1,638.28, 2,457.56 and 815.72 is: 1,223.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,638.28 : 2,457.56 = 815.72 : x
  2. Step 2: Convert to fraction form
    1,638.28/2,457.56 = 815.72/x
  3. Step 3: Cross multiply
    1,638.28x = 2,457.56 × 815.72
  4. Step 4: Simplify right side
    1,638.28x = 2,004,680.84
  5. Step 5: Solve for x
    x = 2,004,680.84/1,638.28
  6. Step 6: Final answer
    x = 1,223.65

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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.