Home / 1,987.66-2,981.50-1,121.98

Finding the Fourth Proportional to 1,987.66, 2,981.50 and 1,121.98

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Solution

The fourth proportional to 1,987.66, 2,981.50 and 1,121.98 is: 1,682.96

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,987.66 : 2,981.50 = 1,121.98 : x
  2. Step 2: Convert to fraction form
    1,987.66/2,981.50 = 1,121.98/x
  3. Step 3: Cross multiply
    1,987.66x = 2,981.50 × 1,121.98
  4. Step 4: Simplify right side
    1,987.66x = 3,345,168.74
  5. Step 5: Solve for x
    x = 3,345,168.74/1,987.66
  6. Step 6: Final answer
    x = 1,682.96

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1.5x scale

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.