Home / 1,278.38-1,917.90-412.71

Finding the Fourth Proportional to 1,278.38, 1,917.90 and 412.71

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Solution

The fourth proportional to 1,278.38, 1,917.90 and 412.71 is: 619.17

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,278.38 : 1,917.90 = 412.71 : x
  2. Step 2: Convert to fraction form
    1,278.38/1,917.90 = 412.71/x
  3. Step 3: Cross multiply
    1,278.38x = 1,917.90 × 412.71
  4. Step 4: Simplify right side
    1,278.38x = 791,536.51
  5. Step 5: Solve for x
    x = 791,536.51/1,278.38
  6. Step 6: Final answer
    x = 619.17

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1.5x scale

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.