Home / 1,989.12-2,980.38-1,218

Finding the Fourth Proportional to 1,989.12, 2,980.38 and 1,218

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Solution

The fourth proportional to 1,989.12, 2,980.38 and 1,218 is: 1,824.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,989.12 : 2,980.38 = 1,218 : x
  2. Step 2: Convert to fraction form
    1,989.12/2,980.38 = 1,218/x
  3. Step 3: Cross multiply
    1,989.12x = 2,980.38 × 1,218
  4. Step 4: Simplify right side
    1,989.12x = 3,630,102.84
  5. Step 5: Solve for x
    x = 3,630,102.84/1,989.12
  6. Step 6: Final answer
    x = 1,824.98

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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.