Home / 1,991.12-2,981.80-1,642.32

Finding the Fourth Proportional to 1,991.12, 2,981.80 and 1,642.32

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Solution

The fourth proportional to 1,991.12, 2,981.80 and 1,642.32 is: 2,459.45

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,991.12 : 2,981.80 = 1,642.32 : x
  2. Step 2: Convert to fraction form
    1,991.12/2,981.80 = 1,642.32/x
  3. Step 3: Cross multiply
    1,991.12x = 2,981.80 × 1,642.32
  4. Step 4: Simplify right side
    1,991.12x = 4,897,069.78
  5. Step 5: Solve for x
    x = 4,897,069.78/1,991.12
  6. Step 6: Final answer
    x = 2,459.45

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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.