Home / 1,278.81-1,918.40-412.83

Finding the Fourth Proportional to 1,278.81, 1,918.40 and 412.83

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Solution

The fourth proportional to 1,278.81, 1,918.40 and 412.83 is: 619.30

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,278.81 : 1,918.40 = 412.83 : x
  2. Step 2: Convert to fraction form
    1,278.81/1,918.40 = 412.83/x
  3. Step 3: Cross multiply
    1,278.81x = 1,918.40 × 412.83
  4. Step 4: Simplify right side
    1,278.81x = 791,971.01
  5. Step 5: Solve for x
    x = 791,971.01/1,278.81
  6. Step 6: Final answer
    x = 619.30

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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.