Home / 1,539.60-2,309.40-1,420.80

Finding the Fourth Proportional to 1,539.60, 2,309.40 and 1,420.80

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Solution

The fourth proportional to 1,539.60, 2,309.40 and 1,420.80 is: 2,131.20

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,539.60 : 2,309.40 = 1,420.80 : x
  2. Step 2: Convert to fraction form
    1,539.60/2,309.40 = 1,420.80/x
  3. Step 3: Cross multiply
    1,539.60x = 2,309.40 × 1,420.80
  4. Step 4: Simplify right side
    1,539.60x = 3,281,195.52
  5. Step 5: Solve for x
    x = 3,281,195.52/1,539.60
  6. Step 6: Final answer
    x = 2,131.20

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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.