Home / 1,386.09-2,079.15-412.20

Finding the Fourth Proportional to 1,386.09, 2,079.15 and 412.20

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Solution

The fourth proportional to 1,386.09, 2,079.15 and 412.20 is: 618.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,386.09 : 2,079.15 = 412.20 : x
  2. Step 2: Convert to fraction form
    1,386.09/2,079.15 = 412.20/x
  3. Step 3: Cross multiply
    1,386.09x = 2,079.15 × 412.20
  4. Step 4: Simplify right side
    1,386.09x = 857,025.63
  5. Step 5: Solve for x
    x = 857,025.63/1,386.09
  6. Step 6: Final answer
    x = 618.30

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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.