Home / 1,315.21-1,969.75-664.38

Finding the Fourth Proportional to 1,315.21, 1,969.75 and 664.38

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Solution

The fourth proportional to 1,315.21, 1,969.75 and 664.38 is: 995.02

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,315.21 : 1,969.75 = 664.38 : x
  2. Step 2: Convert to fraction form
    1,315.21/1,969.75 = 664.38/x
  3. Step 3: Cross multiply
    1,315.21x = 1,969.75 × 664.38
  4. Step 4: Simplify right side
    1,315.21x = 1,308,662.51
  5. Step 5: Solve for x
    x = 1,308,662.51/1,315.21
  6. Step 6: Final answer
    x = 995.02

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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.