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Finding the Fourth Proportional to 719.88, 990.36 and 631.14

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Solution

The fourth proportional to 719.88, 990.36 and 631.14 is: 868.28

Step by Step Solution

  1. Step 1: Write the proportion equation
    719.88 : 990.36 = 631.14 : x
  2. Step 2: Convert to fraction form
    719.88/990.36 = 631.14/x
  3. Step 3: Cross multiply
    719.88x = 990.36 × 631.14
  4. Step 4: Simplify right side
    719.88x = 625,055.81
  5. Step 5: Solve for x
    x = 625,055.81/719.88
  6. Step 6: Final answer
    x = 868.28

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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.