Home / 259.28-388.93-105.20

Finding the Fourth Proportional to 259.28, 388.93 and 105.20

Calculator

Solution

The fourth proportional to 259.28, 388.93 and 105.20 is: 157.81

Step by Step Solution

  1. Step 1: Write the proportion equation
    259.28 : 388.93 = 105.20 : x
  2. Step 2: Convert to fraction form
    259.28/388.93 = 105.20/x
  3. Step 3: Cross multiply
    259.28x = 388.93 × 105.20
  4. Step 4: Simplify right side
    259.28x = 40,915.44
  5. Step 5: Solve for x
    x = 40,915.44/259.28
  6. Step 6: Final answer
    x = 157.81

Related Problems

Find fourth proportional to 129.64, 194.47 and 52.60
Half scale
Find fourth proportional to 518.55, 777.86 and 210.40
Double scale
Find fourth proportional to 260.28, 390.43 and 106.20
Similar ratio
Find fourth proportional to 388.91, 583.40 and 157.80
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.