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Finding the Fourth Proportional to 615.40, 921.66 and 485.08

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Solution

The fourth proportional to 615.40, 921.66 and 485.08 is: 726.48

Step by Step Solution

  1. Step 1: Write the proportion equation
    615.40 : 921.66 = 485.08 : x
  2. Step 2: Convert to fraction form
    615.40/921.66 = 485.08/x
  3. Step 3: Cross multiply
    615.40x = 921.66 × 485.08
  4. Step 4: Simplify right side
    615.40x = 447,078.83
  5. Step 5: Solve for x
    x = 447,078.83/615.40
  6. Step 6: Final answer
    x = 726.48

Related Problems

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Half scale
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Double scale
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Similar ratio
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1.5x scale

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.