Home / 1,680.08-2,519.78-639.36

Finding the Fourth Proportional to 1,680.08, 2,519.78 and 639.36

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Solution

The fourth proportional to 1,680.08, 2,519.78 and 639.36 is: 958.91

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,680.08 : 2,519.78 = 639.36 : x
  2. Step 2: Convert to fraction form
    1,680.08/2,519.78 = 639.36/x
  3. Step 3: Cross multiply
    1,680.08x = 2,519.78 × 639.36
  4. Step 4: Simplify right side
    1,680.08x = 1,611,043.34
  5. Step 5: Solve for x
    x = 1,611,043.34/1,680.08
  6. Step 6: Final answer
    x = 958.91

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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.