Home / 1,427.12-2,138.92-646.90

Finding the Fourth Proportional to 1,427.12, 2,138.92 and 646.90

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Solution

The fourth proportional to 1,427.12, 2,138.92 and 646.90 is: 969.56

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,427.12 : 2,138.92 = 646.90 : x
  2. Step 2: Convert to fraction form
    1,427.12/2,138.92 = 646.90/x
  3. Step 3: Cross multiply
    1,427.12x = 2,138.92 × 646.90
  4. Step 4: Simplify right side
    1,427.12x = 1,383,676.05
  5. Step 5: Solve for x
    x = 1,383,676.05/1,427.12
  6. Step 6: Final answer
    x = 969.56

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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.