Home / 1,987.12-2,977.08-830.80

Finding the Fourth Proportional to 1,987.12, 2,977.08 and 830.80

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Solution

The fourth proportional to 1,987.12, 2,977.08 and 830.80 is: 1,244.69

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,987.12 : 2,977.08 = 830.80 : x
  2. Step 2: Convert to fraction form
    1,987.12/2,977.08 = 830.80/x
  3. Step 3: Cross multiply
    1,987.12x = 2,977.08 × 830.80
  4. Step 4: Simplify right side
    1,987.12x = 2,473,358.06
  5. Step 5: Solve for x
    x = 2,473,358.06/1,987.12
  6. Step 6: Final answer
    x = 1,244.69

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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.