Home / 1,218.27-1,681.65-721.35

Finding the Fourth Proportional to 1,218.27, 1,681.65 and 721.35

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Solution

The fourth proportional to 1,218.27, 1,681.65 and 721.35 is: 995.72

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,218.27 : 1,681.65 = 721.35 : x
  2. Step 2: Convert to fraction form
    1,218.27/1,681.65 = 721.35/x
  3. Step 3: Cross multiply
    1,218.27x = 1,681.65 × 721.35
  4. Step 4: Simplify right side
    1,218.27x = 1,213,058.23
  5. Step 5: Solve for x
    x = 1,213,058.23/1,218.27
  6. Step 6: Final answer
    x = 995.72

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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.