Home / 1,640.20-2,261.96-1,221.60

Finding the Fourth Proportional to 1,640.20, 2,261.96 and 1,221.60

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Solution

The fourth proportional to 1,640.20, 2,261.96 and 1,221.60 is: 1,684.68

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,640.20 : 2,261.96 = 1,221.60 : x
  2. Step 2: Convert to fraction form
    1,640.20/2,261.96 = 1,221.60/x
  3. Step 3: Cross multiply
    1,640.20x = 2,261.96 × 1,221.60
  4. Step 4: Simplify right side
    1,640.20x = 2,763,210.34
  5. Step 5: Solve for x
    x = 2,763,210.34/1,640.20
  6. Step 6: Final answer
    x = 1,684.68

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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.