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Finding the Fourth Proportional to 691.18, 948.26 and 685.51

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Solution

The fourth proportional to 691.18, 948.26 and 685.51 is: 940.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    691.18 : 948.26 = 685.51 : x
  2. Step 2: Convert to fraction form
    691.18/948.26 = 685.51/x
  3. Step 3: Cross multiply
    691.18x = 948.26 × 685.51
  4. Step 4: Simplify right side
    691.18x = 650,041.06
  5. Step 5: Solve for x
    x = 650,041.06/691.18
  6. Step 6: Final answer
    x = 940.48

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.37) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.