Home / 1,989.20-2,742.51-1,279.77

Finding the Fourth Proportional to 1,989.20, 2,742.51 and 1,279.77

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Solution

The fourth proportional to 1,989.20, 2,742.51 and 1,279.77 is: 1,764.42

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,989.20 : 2,742.51 = 1,279.77 : x
  2. Step 2: Convert to fraction form
    1,989.20/2,742.51 = 1,279.77/x
  3. Step 3: Cross multiply
    1,989.20x = 2,742.51 × 1,279.77
  4. Step 4: Simplify right side
    1,989.20x = 3,509,782.02
  5. Step 5: Solve for x
    x = 3,509,782.02/1,989.20
  6. Step 6: Final answer
    x = 1,764.42

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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.