Home / 1,280.28-1,766.48-720.64

Finding the Fourth Proportional to 1,280.28, 1,766.48 and 720.64

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Solution

The fourth proportional to 1,280.28, 1,766.48 and 720.64 is: 994.31

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.28 : 1,766.48 = 720.64 : x
  2. Step 2: Convert to fraction form
    1,280.28/1,766.48 = 720.64/x
  3. Step 3: Cross multiply
    1,280.28x = 1,766.48 × 720.64
  4. Step 4: Simplify right side
    1,280.28x = 1,272,996.15
  5. Step 5: Solve for x
    x = 1,272,996.15/1,280.28
  6. Step 6: Final answer
    x = 994.31

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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.