Finding the Fourth Proportional to 81.36, 121.95 and 35.70
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Solution
The fourth proportional to 81.36, 121.95 and 35.70 is: 53.51
Step by Step Solution
- Step 1: Write the proportion equation
81.36 : 121.95 = 35.70 : x - Step 2: Convert to fraction form
81.36/121.95 = 35.70/x - Step 3: Cross multiply
81.36x = 121.95 × 35.70 - Step 4: Simplify right side
81.36x = 4,353.62 - Step 5: Solve for x
x = 4,353.62/81.36 - Step 6: Final answer
x = 53.51
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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.