Home / 1,389.36-2,070.79-1,311.52

Finding the Fourth Proportional to 1,389.36, 2,070.79 and 1,311.52

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Solution

The fourth proportional to 1,389.36, 2,070.79 and 1,311.52 is: 1,954.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,389.36 : 2,070.79 = 1,311.52 : x
  2. Step 2: Convert to fraction form
    1,389.36/2,070.79 = 1,311.52/x
  3. Step 3: Cross multiply
    1,389.36x = 2,070.79 × 1,311.52
  4. Step 4: Simplify right side
    1,389.36x = 2,715,882.50
  5. Step 5: Solve for x
    x = 2,715,882.50/1,389.36
  6. Step 6: Final answer
    x = 1,954.77

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.