Home / 1,287.36-1,930.80-824.40

Finding the Fourth Proportional to 1,287.36, 1,930.80 and 824.40

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Solution

The fourth proportional to 1,287.36, 1,930.80 and 824.40 is: 1,236.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,287.36 : 1,930.80 = 824.40 : x
  2. Step 2: Convert to fraction form
    1,287.36/1,930.80 = 824.40/x
  3. Step 3: Cross multiply
    1,287.36x = 1,930.80 × 824.40
  4. Step 4: Simplify right side
    1,287.36x = 1,591,751.52
  5. Step 5: Solve for x
    x = 1,591,751.52/1,287.36
  6. Step 6: Final answer
    x = 1,236.45

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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.