Home / 1,284.12-1,771.40-989.28

Finding the Fourth Proportional to 1,284.12, 1,771.40 and 989.28

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Solution

The fourth proportional to 1,284.12, 1,771.40 and 989.28 is: 1,364.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,284.12 : 1,771.40 = 989.28 : x
  2. Step 2: Convert to fraction form
    1,284.12/1,771.40 = 989.28/x
  3. Step 3: Cross multiply
    1,284.12x = 1,771.40 × 989.28
  4. Step 4: Simplify right side
    1,284.12x = 1,752,410.59
  5. Step 5: Solve for x
    x = 1,752,410.59/1,284.12
  6. Step 6: Final answer
    x = 1,364.68

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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.