Finding the Fourth Proportional to 858.99, 1,290 and 639.68
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Solution
The fourth proportional to 858.99, 1,290 and 639.68 is: 960.64
Step by Step Solution
- Step 1: Write the proportion equation
858.99 : 1,290 = 639.68 : x - Step 2: Convert to fraction form
858.99/1,290 = 639.68/x - Step 3: Cross multiply
858.99x = 1,290 × 639.68 - Step 4: Simplify right side
858.99x = 825,180.75 - Step 5: Solve for x
x = 825,180.75/858.99 - Step 6: Final answer
x = 960.64
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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.