Finding the Fourth Proportional to 129.21, 178.31 and 70.99
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Solution
The fourth proportional to 129.21, 178.31 and 70.99 is: 97.97
Step by Step Solution
- Step 1: Write the proportion equation
129.21 : 178.31 = 70.99 : x - Step 2: Convert to fraction form
129.21/178.31 = 70.99/x - Step 3: Cross multiply
129.21x = 178.31 × 70.99 - Step 4: Simplify right side
129.21x = 12,658.67 - Step 5: Solve for x
x = 12,658.67/129.21 - Step 6: Final answer
x = 97.97
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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.