20/3848–12Not a printed formula in Handbook 10.6 Mathematics pp. 36–63 or Engineering Probability and Statistics pp. 64–85
1. Quadratic Formula2. Law of Cosines3. Standard Normal z-Score4. Law of Sines5. Power Rule6. Definite Integral of a Power7. Dot (Scalar) Product8. Cross Product Magnitude9. Sample Standard Deviation10. Binomial Probability11. z Confidence Interval for the Mean12. Circle: Area, Circumference, Arc13. First-Order Linear DE14. Trapezoidal Rule15. Linear Least Squares16. Poisson Probability Mass Function17. Newton–Raphson Iteration18. 2×2 Determinant and Inverse19. Combinations C(n,k)20. Linear Interpolation21. Second-Order Linear DE (Constant Coeff.)22. Exponential Growth and Decay23. Straight Line24. Mean, Median, and Mode25. Addition Rule and Independence26. Derivative of ln and e^u27. Vector Length and Direction Cosines

Handbook formula

Linear Interpolation

Straight-line interpolation between two known points is a reading method, not a printed formula in Handbook 10.6 Mathematics (pp. 36–63) or Engineering Probability and Statistics (pp. 64–85). The (F/P) numbers below are an original teaching example, not a handbook table. Do not extrapolate unless the problem allows it.

First tabulated point
Second tabulated point

Step-by-step solved example

(i,F/P): (6%,1.338) and (8%,1.469). Estimate F/P at 7%.

6%, 1.3388%, 1.469Replay
Tabulated y vs x — interpolate along the straight segment between two stations.

  1. 1. Fraction

    Halfway in i, so halfway in factor if linear in i.

  2. 2. Interpolate

    1.338+0.5(1.469−1.338)=1.4035.

Answer: ≈ 1.404

10 practice questions

0/10 correct

1.y(3) between (2,10) and (6,18) is

2.Extrapolation is

3.At the midpoint, y equals

4.Log interpolation is used when

5.(10,4) and (20,9): y(12) =

6.If x=x0, the formula returns

7.Bilinear interpolation needs

8.A 4-point Lagrange polynomial vs linear

9.Units of interpolated y are

10.(0,100) and (10,80): y(4) =