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Finding the Fourth Proportional to 990.03, 1,485.05 and 412.91

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Solution

The fourth proportional to 990.03, 1,485.05 and 412.91 is: 619.37

Step by Step Solution

  1. Step 1: Write the proportion equation
    990.03 : 1,485.05 = 412.91 : x
  2. Step 2: Convert to fraction form
    990.03/1,485.05 = 412.91/x
  3. Step 3: Cross multiply
    990.03x = 1,485.05 × 412.91
  4. Step 4: Simplify right side
    990.03x = 613,192.00
  5. Step 5: Solve for x
    x = 613,192.00/990.03
  6. Step 6: Final answer
    x = 619.37

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Double scale
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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.