Home / 2.12-3.15-2

Finding the Fourth Proportional to 2.12, 3.15 and 2

Calculator

Solution

The fourth proportional to 2.12, 3.15 and 2 is: 2.98

Step by Step Solution

  1. Step 1: Write the proportion equation
    2.12 : 3.15 = 2 : x
  2. Step 2: Convert to fraction form
    2.12/3.15 = 2/x
  3. Step 3: Cross multiply
    2.12x = 3.15 × 2
  4. Step 4: Simplify right side
    2.12x = 6.30
  5. Step 5: Solve for x
    x = 6.30/2.12
  6. Step 6: Final answer
    x = 2.98

Related Problems

Find fourth proportional to 1.06, 1.58 and 1
Half scale
Find fourth proportional to 4.23, 6.30 and 4
Double scale
Find fourth proportional to 3.12, 4.64 and 3
Similar ratio
Find fourth proportional to 3.17, 4.73 and 3
1.5x scale

Why These Related Problems?

These problems maintain the same ratio (1.49) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.