Home / 1,280.05-1,766.47-720.51

Finding the Fourth Proportional to 1,280.05, 1,766.47 and 720.51

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Solution

The fourth proportional to 1,280.05, 1,766.47 and 720.51 is: 994.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,280.05 : 1,766.47 = 720.51 : x
  2. Step 2: Convert to fraction form
    1,280.05/1,766.47 = 720.51/x
  3. Step 3: Cross multiply
    1,280.05x = 1,766.47 × 720.51
  4. Step 4: Simplify right side
    1,280.05x = 1,272,759.30
  5. Step 5: Solve for x
    x = 1,272,759.30/1,280.05
  6. Step 6: Final answer
    x = 994.30

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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.