Home / 1,284.40-1,926.78-407.15

Finding the Fourth Proportional to 1,284.40, 1,926.78 and 407.15

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Solution

The fourth proportional to 1,284.40, 1,926.78 and 407.15 is: 610.78

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,284.40 : 1,926.78 = 407.15 : x
  2. Step 2: Convert to fraction form
    1,284.40/1,926.78 = 407.15/x
  3. Step 3: Cross multiply
    1,284.40x = 1,926.78 × 407.15
  4. Step 4: Simplify right side
    1,284.40x = 784,476.81
  5. Step 5: Solve for x
    x = 784,476.81/1,284.40
  6. Step 6: Final answer
    x = 610.78

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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.