Home / 1,109.40-1,664.26-378.78

Finding the Fourth Proportional to 1,109.40, 1,664.26 and 378.78

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Solution

The fourth proportional to 1,109.40, 1,664.26 and 378.78 is: 568.22

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,109.40 : 1,664.26 = 378.78 : x
  2. Step 2: Convert to fraction form
    1,109.40/1,664.26 = 378.78/x
  3. Step 3: Cross multiply
    1,109.40x = 1,664.26 × 378.78
  4. Step 4: Simplify right side
    1,109.40x = 630,386.51
  5. Step 5: Solve for x
    x = 630,386.51/1,109.40
  6. Step 6: Final answer
    x = 568.22

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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.