Home / 1,278.40-1,917.90-456.76

Finding the Fourth Proportional to 1,278.40, 1,917.90 and 456.76

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Solution

The fourth proportional to 1,278.40, 1,917.90 and 456.76 is: 685.25

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,278.40 : 1,917.90 = 456.76 : x
  2. Step 2: Convert to fraction form
    1,278.40/1,917.90 = 456.76/x
  3. Step 3: Cross multiply
    1,278.40x = 1,917.90 × 456.76
  4. Step 4: Simplify right side
    1,278.40x = 876,020.00
  5. Step 5: Solve for x
    x = 876,020.00/1,278.40
  6. Step 6: Final answer
    x = 685.25

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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.