Home / 1,987.04-2,743.52-1,390.80

Finding the Fourth Proportional to 1,987.04, 2,743.52 and 1,390.80

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Solution

The fourth proportional to 1,987.04, 2,743.52 and 1,390.80 is: 1,920.29

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,987.04 : 2,743.52 = 1,390.80 : x
  2. Step 2: Convert to fraction form
    1,987.04/2,743.52 = 1,390.80/x
  3. Step 3: Cross multiply
    1,987.04x = 2,743.52 × 1,390.80
  4. Step 4: Simplify right side
    1,987.04x = 3,815,687.62
  5. Step 5: Solve for x
    x = 3,815,687.62/1,987.04
  6. Step 6: Final answer
    x = 1,920.29

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.