Home / 1,287.40-1,920.77-1,148.80

Finding the Fourth Proportional to 1,287.40, 1,920.77 and 1,148.80

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Solution

The fourth proportional to 1,287.40, 1,920.77 and 1,148.80 is: 1,713.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,287.40 : 1,920.77 = 1,148.80 : x
  2. Step 2: Convert to fraction form
    1,287.40/1,920.77 = 1,148.80/x
  3. Step 3: Cross multiply
    1,287.40x = 1,920.77 × 1,148.80
  4. Step 4: Simplify right side
    1,287.40x = 2,206,580.58
  5. Step 5: Solve for x
    x = 2,206,580.58/1,287.40
  6. Step 6: Final answer
    x = 1,713.98

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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.