Home / 1,389.80-1,918.41-800.57

Finding the Fourth Proportional to 1,389.80, 1,918.41 and 800.57

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Solution

The fourth proportional to 1,389.80, 1,918.41 and 800.57 is: 1,105.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,389.80 : 1,918.41 = 800.57 : x
  2. Step 2: Convert to fraction form
    1,389.80/1,918.41 = 800.57/x
  3. Step 3: Cross multiply
    1,389.80x = 1,918.41 × 800.57
  4. Step 4: Simplify right side
    1,389.80x = 1,535,824.29
  5. Step 5: Solve for x
    x = 1,535,824.29/1,389.80
  6. Step 6: Final answer
    x = 1,105.07

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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.