Home / 780-1,076.40-504.48

Finding the Fourth Proportional to 780, 1,076.40 and 504.48

Calculator

Solution

The fourth proportional to 780, 1,076.40 and 504.48 is: 696.18

Step by Step Solution

  1. Step 1: Write the proportion equation
    780 : 1,076.40 = 504.48 : x
  2. Step 2: Convert to fraction form
    780/1,076.40 = 504.48/x
  3. Step 3: Cross multiply
    780x = 1,076.40 × 504.48
  4. Step 4: Simplify right side
    780x = 543,022.27
  5. Step 5: Solve for x
    x = 543,022.27/780
  6. Step 6: Final answer
    x = 696.18

Related Problems

Find fourth proportional to 390, 538.20 and 252.24
Half scale
Find fourth proportional to 1,560, 2,152.80 and 1,008.96
Double scale
Find fourth proportional to 781, 1,077.78 and 505.48
Similar ratio
Find fourth proportional to 1,170, 1,614.60 and 756.72
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.