Finding the Fourth Proportional to 1,385.25, 1,911.65 and 764.25
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Solution
The fourth proportional to 1,385.25, 1,911.65 and 764.25 is: 1,054.67
Step by Step Solution
- Step 1: Write the proportion equation
1,385.25 : 1,911.65 = 764.25 : x - Step 2: Convert to fraction form
1,385.25/1,911.65 = 764.25/x - Step 3: Cross multiply
1,385.25x = 1,911.65 × 764.25 - Step 4: Simplify right side
1,385.25x = 1,460,974.69 - Step 5: Solve for x
x = 1,460,974.69/1,385.25 - Step 6: Final answer
x = 1,054.67
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1.5x scale
Why These Related Problems?
These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.