Home / 1,389.39-2,084.07-1,320.18

Finding the Fourth Proportional to 1,389.39, 2,084.07 and 1,320.18

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Solution

The fourth proportional to 1,389.39, 2,084.07 and 1,320.18 is: 1,980.26

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,389.39 : 2,084.07 = 1,320.18 : x
  2. Step 2: Convert to fraction form
    1,389.39/2,084.07 = 1,320.18/x
  3. Step 3: Cross multiply
    1,389.39x = 2,084.07 × 1,320.18
  4. Step 4: Simplify right side
    1,389.39x = 2,751,347.53
  5. Step 5: Solve for x
    x = 2,751,347.53/1,389.39
  6. Step 6: Final answer
    x = 1,980.26

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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.