Finding the Fourth Proportional to 861, 1,293.64 and 553
Calculator
Solution
The fourth proportional to 861, 1,293.64 and 553 is: 830.87
Step by Step Solution
- Step 1: Write the proportion equation
861 : 1,293.64 = 553 : x - Step 2: Convert to fraction form
861/1,293.64 = 553/x - Step 3: Cross multiply
861x = 1,293.64 × 553 - Step 4: Simplify right side
861x = 715,382.92 - Step 5: Solve for x
x = 715,382.92/861 - Step 6: Final answer
x = 830.87
Related Problems
Find fourth proportional to 430.50, 646.82 and 276.50
Half scale
Find fourth proportional to 1,722, 2,587.28 and 1,106
Double scale
Find fourth proportional to 862, 1,295.14 and 554
Similar ratio
Find fourth proportional to 1,291.50, 1,940.46 and 829.50
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.