Finding the Fourth Proportional to 85.62, 128.48 and 39.98
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Solution
The fourth proportional to 85.62, 128.48 and 39.98 is: 59.99
Step by Step Solution
- Step 1: Write the proportion equation
85.62 : 128.48 = 39.98 : x - Step 2: Convert to fraction form
85.62/128.48 = 39.98/x - Step 3: Cross multiply
85.62x = 128.48 × 39.98 - Step 4: Simplify right side
85.62x = 5,136.63 - Step 5: Solve for x
x = 5,136.63/85.62 - Step 6: Final answer
x = 59.99
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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.