Home / 1,985.78-2,979.84-1,120.70

Finding the Fourth Proportional to 1,985.78, 2,979.84 and 1,120.70

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Solution

The fourth proportional to 1,985.78, 2,979.84 and 1,120.70 is: 1,681.71

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,985.78 : 2,979.84 = 1,120.70 : x
  2. Step 2: Convert to fraction form
    1,985.78/2,979.84 = 1,120.70/x
  3. Step 3: Cross multiply
    1,985.78x = 2,979.84 × 1,120.70
  4. Step 4: Simplify right side
    1,985.78x = 3,339,506.69
  5. Step 5: Solve for x
    x = 3,339,506.69/1,985.78
  6. Step 6: Final answer
    x = 1,681.71

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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.