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Finding the Fourth Proportional to 681.12, 1,015.47 and 615.51

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Solution

The fourth proportional to 681.12, 1,015.47 and 615.51 is: 917.65

Step by Step Solution

  1. Step 1: Write the proportion equation
    681.12 : 1,015.47 = 615.51 : x
  2. Step 2: Convert to fraction form
    681.12/1,015.47 = 615.51/x
  3. Step 3: Cross multiply
    681.12x = 1,015.47 × 615.51
  4. Step 4: Simplify right side
    681.12x = 625,031.94
  5. Step 5: Solve for x
    x = 625,031.94/681.12
  6. Step 6: Final answer
    x = 917.65

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.