Home / 1,221.30-1,683.45-1,205.10

Finding the Fourth Proportional to 1,221.30, 1,683.45 and 1,205.10

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Solution

The fourth proportional to 1,221.30, 1,683.45 and 1,205.10 is: 1,661.12

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,221.30 : 1,683.45 = 1,205.10 : x
  2. Step 2: Convert to fraction form
    1,221.30/1,683.45 = 1,205.10/x
  3. Step 3: Cross multiply
    1,221.30x = 1,683.45 × 1,205.10
  4. Step 4: Simplify right side
    1,221.30x = 2,028,725.60
  5. Step 5: Solve for x
    x = 2,028,725.60/1,221.30
  6. Step 6: Final answer
    x = 1,661.12

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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.