Calculators — Guides & Articles

• How to Calculate LCM and GCF in One Step

  Published 2026-08-21

  Calculate LCM and GCF together from any list of integers using lcm(a, b) = |a × b| ÷ GCF(a, b). See a worked example with 4, 6, 8 and a free tool with steps.

  

• How to Calculate the Knapsack Problem Step by Step

  Published 2026-08-20

  Calculate any 0/1 knapsack problem step by step. Enter whole-number capacity, items, weights, and values to find the maximum-value subset.

  

• How to Estimate Ideal Weight for Children by Age

  Published 2026-08-20

  Children's ideal weight uses age-based formulas and growth curves, not adult height-only equations. See when the calculator applies and when it doesn't.

  

• How to Calculate Regular Hexagon Area from One Side

  Published 2026-08-20

  Find a regular hexagon's area from one side using A = (3√3/2)·s², plus perimeter, apothem, and circumradius — a quick worked guide.

  

• Hemisphere by Sun: How to Determine Volume and Area

  Published 2026-08-20

  Determine a hemisphere's volume and surface areas from a single radius. Get curved, base, and total area plus V = (2/3)πr³ with the free calculator.

  

• How to Calculate Your University GPA on the 4.0 Scale

  Published 2026-08-20

  Your university GPA is a credit-weighted average on the 4.0 scale. See the exact formula, a worked example, letter-grade point values, and a free tool.

  

• How to Find the GCF of 3 Numbers in One Step

  Published 2026-08-20

  Calculate the greatest common factor (GCF) of three numbers instantly using a free online tool that shows the exact steps and works for any integers.

  

• How to Figure Gas Mileage Cost for Work Reimbursement

  Published 2026-08-20

  Figure out your gas mileage cost for work driving: measure your real MPG, multiply by your gas price. A clean method for reimbursement and tax logs.

  

• How to Convert Frequency to Hertz: Methods and Formulas

  Published 2026-08-19

  Convert any frequency to hertz with SI formulas or an online calculator. Covers Hz, kHz, MHz, GHz, THz, rad/s, rpm, BPM and deg/s with worked examples.

  

• How to Convert Force Into Torque — The Formula

  Published 2026-08-19

  Force and torque aren't interchangeable units — you need a lever-arm distance. Here's the formula and how to convert force units (N, lbf, kgf, kip) first.