Home / 3,945-5,917.50-1,209

Finding the Fourth Proportional to 3,945, 5,917.50 and 1,209

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Solution

The fourth proportional to 3,945, 5,917.50 and 1,209 is: 1,813.50

Step by Step Solution

  1. Step 1: Write the proportion equation
    3,945 : 5,917.50 = 1,209 : x
  2. Step 2: Convert to fraction form
    3,945/5,917.50 = 1,209/x
  3. Step 3: Cross multiply
    3,945x = 5,917.50 × 1,209
  4. Step 4: Simplify right side
    3,945x = 7,154,257.50
  5. Step 5: Solve for x
    x = 7,154,257.50/3,945
  6. Step 6: Final answer
    x = 1,813.50

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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.