Home / 1,388.95-2,082.21-1,311.59

Finding the Fourth Proportional to 1,388.95, 2,082.21 and 1,311.59

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Solution

The fourth proportional to 1,388.95, 2,082.21 and 1,311.59 is: 1,966.24

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,388.95 : 2,082.21 = 1,311.59 : x
  2. Step 2: Convert to fraction form
    1,388.95/2,082.21 = 1,311.59/x
  3. Step 3: Cross multiply
    1,388.95x = 2,082.21 × 1,311.59
  4. Step 4: Simplify right side
    1,388.95x = 2,731,006.10
  5. Step 5: Solve for x
    x = 2,731,006.10/1,388.95
  6. Step 6: Final answer
    x = 1,966.24

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1.5x scale

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.