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Finding the Fourth Proportional to 718.47, 990.63 and 644.76

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Solution

The fourth proportional to 718.47, 990.63 and 644.76 is: 889.00

Step by Step Solution

  1. Step 1: Write the proportion equation
    718.47 : 990.63 = 644.76 : x
  2. Step 2: Convert to fraction form
    718.47/990.63 = 644.76/x
  3. Step 3: Cross multiply
    718.47x = 990.63 × 644.76
  4. Step 4: Simplify right side
    718.47x = 638,718.60
  5. Step 5: Solve for x
    x = 638,718.60/718.47
  6. Step 6: Final answer
    x = 889.00

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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.