Mental maths · lesson 8 of 28 · free

Multiply 2-digit by 1-digit, tens first — Mental Maths Mastery

Start with the tens: it gives the big part of the answer straight away. Then multiply the ones and add — the same left-to-right idea as adding.

How to do it in your head

Tens first — “multiply the tens, keep it, then add the ones”

  1. Split the 2-digit number into tens and ones.
  2. Multiply the tens and keep that answer in your head.
  3. Multiply the ones and add.

Use it for: Shopping totals (7 pens at ₹68), quick checks, and every bigger multiplication.

Worked example: 68 × 7 = 476

  1. Split 68 into 60 and 8.
  2. 60 × 7 = 420 and 8 × 7 = 56.
  3. 420 + 56 = 476.

Check: 68 × 7 = 70 × 7 − 2 × 7 = 490 − 14 = 476 ✓

✏️ Practice

Work it out in your head or on paper, type the answer and press Check. Stuck? Press “Show me how”.

Right: 0 · Tried: 0

🏁 Lesson 8 test

20 questions. Check each answer, then go to the next one. Get 16 or more right to pass.

🏅 Sign in with Google to earn the 🚀 Tens-First Rocket badge when you pass — and a certificate when you finish all 6 lessons of Part 2 · Mental multiplication & division. You can still take the test without signing in.

🖨️ Mental Multiplication Worksheet for Class 3 and 4

✨ Free AI tutor

Ask the AI tutor about this lesson

Why does it work? When should you use it? Ask in English, मराठी or हिंदी.

Sign in with Google to ask Free — 20 questions a day.

👩‍🏫 Mental maths classes near you — online or at home

Prefer a real teacher? TalentJR teachers take live online classes anywhere in India and visit homes in selected cities. Tell us what you need and our team will call you with timings and fees.

Live online classesSmall groups or 1:1 with a teacher, from home, any city.
Teacher at homeA TalentJR teacher visits your home (selected cities).
At a centreClasses at a TalentJR partner centre near you, where available.
Badges, certificates & gifts A badge for every lesson you pass, a certificate for every part you finish, plus TalentJR Points for daily practice. Tables & multiplication Still learning tables? Start with Tables & Multiplication Mastery.