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Finding the Fourth Proportional to 681.90, 940.68 and 485.52

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Solution

The fourth proportional to 681.90, 940.68 and 485.52 is: 669.77

Step by Step Solution

  1. Step 1: Write the proportion equation
    681.90 : 940.68 = 485.52 : x
  2. Step 2: Convert to fraction form
    681.90/940.68 = 485.52/x
  3. Step 3: Cross multiply
    681.90x = 940.68 × 485.52
  4. Step 4: Simplify right side
    681.90x = 456,718.95
  5. Step 5: Solve for x
    x = 456,718.95/681.90
  6. Step 6: Final answer
    x = 669.77

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1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.