Home / 1,987.12-2,741.34-1,288.36

Finding the Fourth Proportional to 1,987.12, 2,741.34 and 1,288.36

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Solution

The fourth proportional to 1,987.12, 2,741.34 and 1,288.36 is: 1,777.36

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,987.12 : 2,741.34 = 1,288.36 : x
  2. Step 2: Convert to fraction form
    1,987.12/2,741.34 = 1,288.36/x
  3. Step 3: Cross multiply
    1,987.12x = 2,741.34 × 1,288.36
  4. Step 4: Simplify right side
    1,987.12x = 3,531,832.80
  5. Step 5: Solve for x
    x = 3,531,832.80/1,987.12
  6. Step 6: Final answer
    x = 1,777.36

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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.