Home / 1,412.20-2,118.30-386.20

Finding the Fourth Proportional to 1,412.20, 2,118.30 and 386.20

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Solution

The fourth proportional to 1,412.20, 2,118.30 and 386.20 is: 579.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,412.20 : 2,118.30 = 386.20 : x
  2. Step 2: Convert to fraction form
    1,412.20/2,118.30 = 386.20/x
  3. Step 3: Cross multiply
    1,412.20x = 2,118.30 × 386.20
  4. Step 4: Simplify right side
    1,412.20x = 818,087.46
  5. Step 5: Solve for x
    x = 818,087.46/1,412.20
  6. Step 6: Final answer
    x = 579.30

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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.