Home / 1,415.40-2,119.80-720.96

Finding the Fourth Proportional to 1,415.40, 2,119.80 and 720.96

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Solution

The fourth proportional to 1,415.40, 2,119.80 and 720.96 is: 1,079.76

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,415.40 : 2,119.80 = 720.96 : x
  2. Step 2: Convert to fraction form
    1,415.40/2,119.80 = 720.96/x
  3. Step 3: Cross multiply
    1,415.40x = 2,119.80 × 720.96
  4. Step 4: Simplify right side
    1,415.40x = 1,528,291.01
  5. Step 5: Solve for x
    x = 1,528,291.01/1,415.40
  6. Step 6: Final answer
    x = 1,079.76

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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.