Home / 1,286.02-1,928.82-420.12

Finding the Fourth Proportional to 1,286.02, 1,928.82 and 420.12

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Solution

The fourth proportional to 1,286.02, 1,928.82 and 420.12 is: 630.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,286.02 : 1,928.82 = 420.12 : x
  2. Step 2: Convert to fraction form
    1,286.02/1,928.82 = 420.12/x
  3. Step 3: Cross multiply
    1,286.02x = 1,928.82 × 420.12
  4. Step 4: Simplify right side
    1,286.02x = 810,335.86
  5. Step 5: Solve for x
    x = 810,335.86/1,286.02
  6. Step 6: Final answer
    x = 630.11

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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.