Finding the Fourth Proportional to 81.30, 121.77 and 70.05
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Solution
The fourth proportional to 81.30, 121.77 and 70.05 is: 104.92
Step by Step Solution
- Step 1: Write the proportion equation
81.30 : 121.77 = 70.05 : x - Step 2: Convert to fraction form
81.30/121.77 = 70.05/x - Step 3: Cross multiply
81.30x = 121.77 × 70.05 - Step 4: Simplify right side
81.30x = 8,529.99 - Step 5: Solve for x
x = 8,529.99/81.30 - Step 6: Final answer
x = 104.92
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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.