Finding the Fourth Proportional to 81.24, 121.28 and 70.44
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Solution
The fourth proportional to 81.24, 121.28 and 70.44 is: 105.16
Step by Step Solution
- Step 1: Write the proportion equation
81.24 : 121.28 = 70.44 : x - Step 2: Convert to fraction form
81.24/121.28 = 70.44/x - Step 3: Cross multiply
81.24x = 121.28 × 70.44 - Step 4: Simplify right side
81.24x = 8,542.96 - Step 5: Solve for x
x = 8,542.96/81.24 - Step 6: Final answer
x = 105.16
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Why These Related Problems?
These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.