Home / 1,555.20-2,138.40-1,490.40

Finding the Fourth Proportional to 1,555.20, 2,138.40 and 1,490.40

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Solution

The fourth proportional to 1,555.20, 2,138.40 and 1,490.40 is: 2,049.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,555.20 : 2,138.40 = 1,490.40 : x
  2. Step 2: Convert to fraction form
    1,555.20/2,138.40 = 1,490.40/x
  3. Step 3: Cross multiply
    1,555.20x = 2,138.40 × 1,490.40
  4. Step 4: Simplify right side
    1,555.20x = 3,187,071.36
  5. Step 5: Solve for x
    x = 3,187,071.36/1,555.20
  6. Step 6: Final answer
    x = 2,049.30

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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.