Home / 1,986-2,740.80-1,158

Finding the Fourth Proportional to 1,986, 2,740.80 and 1,158

Calculator

Solution

The fourth proportional to 1,986, 2,740.80 and 1,158 is: 1,598.11

Step by Step Solution

  1. Step 1: Write the proportion equation
    1,986 : 2,740.80 = 1,158 : x
  2. Step 2: Convert to fraction form
    1,986/2,740.80 = 1,158/x
  3. Step 3: Cross multiply
    1,986x = 2,740.80 × 1,158
  4. Step 4: Simplify right side
    1,986x = 3,173,846.40
  5. Step 5: Solve for x
    x = 3,173,846.40/1,986
  6. Step 6: Final answer
    x = 1,598.11

Related Problems

Find fourth proportional to 993, 1,370.40 and 579
Half scale
Find fourth proportional to 3,972, 5,481.60 and 2,316
Double scale
Find fourth proportional to 1,987, 2,742.18 and 1,159
Similar ratio
Find fourth proportional to 2,979, 4,111.20 and 1,737
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.