Home / 1,987.20-2,740.50-1,240.92

Finding the Fourth Proportional to 1,987.20, 2,740.50 and 1,240.92

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Solution

The fourth proportional to 1,987.20, 2,740.50 and 1,240.92 is: 1,711.32

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,987.20 : 2,740.50 = 1,240.92 : x
  2. Step 2: Convert to fraction form
    1,987.20/2,740.50 = 1,240.92/x
  3. Step 3: Cross multiply
    1,987.20x = 2,740.50 × 1,240.92
  4. Step 4: Simplify right side
    1,987.20x = 3,400,741.26
  5. Step 5: Solve for x
    x = 3,400,741.26/1,987.20
  6. Step 6: Final answer
    x = 1,711.32

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Half scale
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Double scale
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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.