Home / 1,284.91-1,918.07-1,129.21

Finding the Fourth Proportional to 1,284.91, 1,918.07 and 1,129.21

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Solution

The fourth proportional to 1,284.91, 1,918.07 and 1,129.21 is: 1,685.64

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,284.91 : 1,918.07 = 1,129.21 : x
  2. Step 2: Convert to fraction form
    1,284.91/1,918.07 = 1,129.21/x
  3. Step 3: Cross multiply
    1,284.91x = 1,918.07 × 1,129.21
  4. Step 4: Simplify right side
    1,284.91x = 2,165,898.18
  5. Step 5: Solve for x
    x = 2,165,898.18/1,284.91
  6. Step 6: Final answer
    x = 1,685.64

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.