Home / 3,478.40-5,218.38-1,287.20

Finding the Fourth Proportional to 3,478.40, 5,218.38 and 1,287.20

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Solution

The fourth proportional to 3,478.40, 5,218.38 and 1,287.20 is: 1,931.09

Step by Step Solution

  1. Step 1: Write the proportion equation
    3,478.40 : 5,218.38 = 1,287.20 : x
  2. Step 2: Convert to fraction form
    3,478.40/5,218.38 = 1,287.20/x
  3. Step 3: Cross multiply
    3,478.40x = 5,218.38 × 1,287.20
  4. Step 4: Simplify right side
    3,478.40x = 6,717,098.74
  5. Step 5: Solve for x
    x = 6,717,098.74/3,478.40
  6. Step 6: Final answer
    x = 1,931.09

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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.