Home / 1,289.20-1,779.07-699.75

Finding the Fourth Proportional to 1,289.20, 1,779.07 and 699.75

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Solution

The fourth proportional to 1,289.20, 1,779.07 and 699.75 is: 965.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,289.20 : 1,779.07 = 699.75 : x
  2. Step 2: Convert to fraction form
    1,289.20/1,779.07 = 699.75/x
  3. Step 3: Cross multiply
    1,289.20x = 1,779.07 × 699.75
  4. Step 4: Simplify right side
    1,289.20x = 1,244,904.23
  5. Step 5: Solve for x
    x = 1,244,904.23/1,289.20
  6. Step 6: Final answer
    x = 965.64

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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.