Home / 1,639.20-2,459.61-666.12

Finding the Fourth Proportional to 1,639.20, 2,459.61 and 666.12

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Solution

The fourth proportional to 1,639.20, 2,459.61 and 666.12 is: 999.51

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,639.20 : 2,459.61 = 666.12 : x
  2. Step 2: Convert to fraction form
    1,639.20/2,459.61 = 666.12/x
  3. Step 3: Cross multiply
    1,639.20x = 2,459.61 × 666.12
  4. Step 4: Simplify right side
    1,639.20x = 1,638,395.41
  5. Step 5: Solve for x
    x = 1,638,395.41/1,639.20
  6. Step 6: Final answer
    x = 999.51

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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.