Finding the Fourth Proportional to 85,689.20, 128,386.17 and 66,720.62
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Solution
The fourth proportional to 85,689.20, 128,386.17 and 66,720.62 is: 99,965.98
Step by Step Solution
- Step 1: Write the proportion equation
85,689.20 : 128,386.17 = 66,720.62 : x - Step 2: Convert to fraction form
85,689.20/128,386.17 = 66,720.62/x - Step 3: Cross multiply
85,689.20x = 128,386.17 × 66,720.62 - Step 4: Simplify right side
85,689.20x = 8,566,004,219.89 - Step 5: Solve for x
x = 8,566,004,219.89/85,689.20 - Step 6: Final answer
x = 99,965.98
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1.5x scale
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.