Home / 1,912.80-2,640.24-1,389.60

Finding the Fourth Proportional to 1,912.80, 2,640.24 and 1,389.60

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Solution

The fourth proportional to 1,912.80, 2,640.24 and 1,389.60 is: 1,918.07

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,912.80 : 2,640.24 = 1,389.60 : x
  2. Step 2: Convert to fraction form
    1,912.80/2,640.24 = 1,389.60/x
  3. Step 3: Cross multiply
    1,912.80x = 2,640.24 × 1,389.60
  4. Step 4: Simplify right side
    1,912.80x = 3,668,877.50
  5. Step 5: Solve for x
    x = 3,668,877.50/1,912.80
  6. Step 6: Final answer
    x = 1,918.07

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1.5x scale

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.