Home / 1,321.40-1,986.90-1,110.20

Finding the Fourth Proportional to 1,321.40, 1,986.90 and 1,110.20

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Solution

The fourth proportional to 1,321.40, 1,986.90 and 1,110.20 is: 1,669.33

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,321.40 : 1,986.90 = 1,110.20 : x
  2. Step 2: Convert to fraction form
    1,321.40/1,986.90 = 1,110.20/x
  3. Step 3: Cross multiply
    1,321.40x = 1,986.90 × 1,110.20
  4. Step 4: Simplify right side
    1,321.40x = 2,205,856.38
  5. Step 5: Solve for x
    x = 2,205,856.38/1,321.40
  6. Step 6: Final answer
    x = 1,669.33

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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.