Home / 1,215.40-1,819.16-666.20

Finding the Fourth Proportional to 1,215.40, 1,819.16 and 666.20

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Solution

The fourth proportional to 1,215.40, 1,819.16 and 666.20 is: 997.14

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,215.40 : 1,819.16 = 666.20 : x
  2. Step 2: Convert to fraction form
    1,215.40/1,819.16 = 666.20/x
  3. Step 3: Cross multiply
    1,215.40x = 1,819.16 × 666.20
  4. Step 4: Simplify right side
    1,215.40x = 1,211,924.39
  5. Step 5: Solve for x
    x = 1,211,924.39/1,215.40
  6. Step 6: Final answer
    x = 997.14

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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.