Finding the Fourth Proportional to 123.89, 170.94 and 86.99
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Solution
The fourth proportional to 123.89, 170.94 and 86.99 is: 120.03
Step by Step Solution
- Step 1: Write the proportion equation
123.89 : 170.94 = 86.99 : x - Step 2: Convert to fraction form
123.89/170.94 = 86.99/x - Step 3: Cross multiply
123.89x = 170.94 × 86.99 - Step 4: Simplify right side
123.89x = 14,870.07 - Step 5: Solve for x
x = 14,870.07/123.89 - Step 6: Final answer
x = 120.03
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These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.