Finding the Fourth Proportional to 57, 85.50 and 19
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Solution
The fourth proportional to 57, 85.50 and 19 is: 28.50
Step by Step Solution
- Step 1: Write the proportion equation
57 : 85.50 = 19 : x - Step 2: Convert to fraction form
57/85.50 = 19/x - Step 3: Cross multiply
57x = 85.50 × 19 - Step 4: Simplify right side
57x = 1,624.50 - Step 5: Solve for x
x = 1,624.50/57 - Step 6: Final answer
x = 28.50
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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.