Home / 1,987.81-2,742.89-1,280.62

Finding the Fourth Proportional to 1,987.81, 2,742.89 and 1,280.62

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Solution

The fourth proportional to 1,987.81, 2,742.89 and 1,280.62 is: 1,767.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,987.81 : 2,742.89 = 1,280.62 : x
  2. Step 2: Convert to fraction form
    1,987.81/2,742.89 = 1,280.62/x
  3. Step 3: Cross multiply
    1,987.81x = 2,742.89 × 1,280.62
  4. Step 4: Simplify right side
    1,987.81x = 3,512,599.79
  5. Step 5: Solve for x
    x = 3,512,599.79/1,987.81
  6. Step 6: Final answer
    x = 1,767.07

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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.