Finding the Fourth Proportional to 128.78, 193.33 and 99.98
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Solution
The fourth proportional to 128.78, 193.33 and 99.98 is: 150.09
Step by Step Solution
- Step 1: Write the proportion equation
128.78 : 193.33 = 99.98 : x - Step 2: Convert to fraction form
128.78/193.33 = 99.98/x - Step 3: Cross multiply
128.78x = 193.33 × 99.98 - Step 4: Simplify right side
128.78x = 19,329.13 - Step 5: Solve for x
x = 19,329.13/128.78 - Step 6: Final answer
x = 150.09
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These problems maintain the same ratio (1.50) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.