Home / 1,221.15-1,685.13-690.04

Finding the Fourth Proportional to 1,221.15, 1,685.13 and 690.04

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Solution

The fourth proportional to 1,221.15, 1,685.13 and 690.04 is: 952.23

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,221.15 : 1,685.13 = 690.04 : x
  2. Step 2: Convert to fraction form
    1,221.15/1,685.13 = 690.04/x
  3. Step 3: Cross multiply
    1,221.15x = 1,685.13 × 690.04
  4. Step 4: Simplify right side
    1,221.15x = 1,162,813.30
  5. Step 5: Solve for x
    x = 1,162,813.30/1,221.15
  6. Step 6: Final answer
    x = 952.23

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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.