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Finding the Fourth Proportional to 940.80, 1,411.20 and 649.20

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Solution

The fourth proportional to 940.80, 1,411.20 and 649.20 is: 973.80

Step by Step Solution

  1. Step 1: Write the proportion equation
    940.80 : 1,411.20 = 649.20 : x
  2. Step 2: Convert to fraction form
    940.80/1,411.20 = 649.20/x
  3. Step 3: Cross multiply
    940.80x = 1,411.20 × 649.20
  4. Step 4: Simplify right side
    940.80x = 916,151.04
  5. Step 5: Solve for x
    x = 916,151.04/940.80
  6. Step 6: Final answer
    x = 973.80

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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.