Finding the Fourth Proportional to 428.15, 642.22 and 103.52
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Solution
The fourth proportional to 428.15, 642.22 and 103.52 is: 155.28
Step by Step Solution
- Step 1: Write the proportion equation
428.15 : 642.22 = 103.52 : x - Step 2: Convert to fraction form
428.15/642.22 = 103.52/x - Step 3: Cross multiply
428.15x = 642.22 × 103.52 - Step 4: Simplify right side
428.15x = 66,482.61 - Step 5: Solve for x
x = 66,482.61/428.15 - Step 6: Final answer
x = 155.28
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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.