Finding the Fourth Proportional to 81.41, 121.08 and 81.15
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Solution
The fourth proportional to 81.41, 121.08 and 81.15 is: 120.70
Step by Step Solution
- Step 1: Write the proportion equation
81.41 : 121.08 = 81.15 : x - Step 2: Convert to fraction form
81.41/121.08 = 81.15/x - Step 3: Cross multiply
81.41x = 121.08 × 81.15 - Step 4: Simplify right side
81.41x = 9,825.49 - Step 5: Solve for x
x = 9,825.49/81.41 - Step 6: Final answer
x = 120.70
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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.