Home / 1,287.96-1,918.65-1,208.28

Finding the Fourth Proportional to 1,287.96, 1,918.65 and 1,208.28

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Solution

The fourth proportional to 1,287.96, 1,918.65 and 1,208.28 is: 1,799.95

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,287.96 : 1,918.65 = 1,208.28 : x
  2. Step 2: Convert to fraction form
    1,287.96/1,918.65 = 1,208.28/x
  3. Step 3: Cross multiply
    1,287.96x = 1,918.65 × 1,208.28
  4. Step 4: Simplify right side
    1,287.96x = 2,318,266.42
  5. Step 5: Solve for x
    x = 2,318,266.42/1,287.96
  6. Step 6: Final answer
    x = 1,799.95

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Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.