Home / 1,427.69-2,139.32-989.79

Finding the Fourth Proportional to 1,427.69, 2,139.32 and 989.79

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Solution

The fourth proportional to 1,427.69, 2,139.32 and 989.79 is: 1,483.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,427.69 : 2,139.32 = 989.79 : x
  2. Step 2: Convert to fraction form
    1,427.69/2,139.32 = 989.79/x
  3. Step 3: Cross multiply
    1,427.69x = 2,139.32 × 989.79
  4. Step 4: Simplify right side
    1,427.69x = 2,117,489.16
  5. Step 5: Solve for x
    x = 2,117,489.16/1,427.69
  6. Step 6: Final answer
    x = 1,483.16

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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.