Home / 1,215.12-1,821.27-520.74

Finding the Fourth Proportional to 1,215.12, 1,821.27 and 520.74

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Solution

The fourth proportional to 1,215.12, 1,821.27 and 520.74 is: 780.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,215.12 : 1,821.27 = 520.74 : x
  2. Step 2: Convert to fraction form
    1,215.12/1,821.27 = 520.74/x
  3. Step 3: Cross multiply
    1,215.12x = 1,821.27 × 520.74
  4. Step 4: Simplify right side
    1,215.12x = 948,408.14
  5. Step 5: Solve for x
    x = 948,408.14/1,215.12
  6. Step 6: Final answer
    x = 780.51

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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.