Home / 1,212.12-1,817.90-390.52

Finding the Fourth Proportional to 1,212.12, 1,817.90 and 390.52

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Solution

The fourth proportional to 1,212.12, 1,817.90 and 390.52 is: 585.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,212.12 : 1,817.90 = 390.52 : x
  2. Step 2: Convert to fraction form
    1,212.12/1,817.90 = 390.52/x
  3. Step 3: Cross multiply
    1,212.12x = 1,817.90 × 390.52
  4. Step 4: Simplify right side
    1,212.12x = 709,926.31
  5. Step 5: Solve for x
    x = 709,926.31/1,212.12
  6. Step 6: Final answer
    x = 585.69

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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.