Home / 1,688.20-2,328.78-989.44

Finding the Fourth Proportional to 1,688.20, 2,328.78 and 989.44

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Solution

The fourth proportional to 1,688.20, 2,328.78 and 989.44 is: 1,364.88

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,688.20 : 2,328.78 = 989.44 : x
  2. Step 2: Convert to fraction form
    1,688.20/2,328.78 = 989.44/x
  3. Step 3: Cross multiply
    1,688.20x = 2,328.78 × 989.44
  4. Step 4: Simplify right side
    1,688.20x = 2,304,188.08
  5. Step 5: Solve for x
    x = 2,304,188.08/1,688.20
  6. Step 6: Final answer
    x = 1,364.88

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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.