Home / 1,987.21-2,739.45-1,240.84

Finding the Fourth Proportional to 1,987.21, 2,739.45 and 1,240.84

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Solution

The fourth proportional to 1,987.21, 2,739.45 and 1,240.84 is: 1,710.55

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,987.21 : 2,739.45 = 1,240.84 : x
  2. Step 2: Convert to fraction form
    1,987.21/2,739.45 = 1,240.84/x
  3. Step 3: Cross multiply
    1,987.21x = 2,739.45 × 1,240.84
  4. Step 4: Simplify right side
    1,987.21x = 3,399,219.14
  5. Step 5: Solve for x
    x = 3,399,219.14/1,987.21
  6. Step 6: Final answer
    x = 1,710.55

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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.