Home / 1,418.30-2,128.17-638.15

Finding the Fourth Proportional to 1,418.30, 2,128.17 and 638.15

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Solution

The fourth proportional to 1,418.30, 2,128.17 and 638.15 is: 957.54

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,418.30 : 2,128.17 = 638.15 : x
  2. Step 2: Convert to fraction form
    1,418.30/2,128.17 = 638.15/x
  3. Step 3: Cross multiply
    1,418.30x = 2,128.17 × 638.15
  4. Step 4: Simplify right side
    1,418.30x = 1,358,083.44
  5. Step 5: Solve for x
    x = 1,358,083.44/1,418.30
  6. Step 6: Final answer
    x = 957.54

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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.