Maths using Squares to help Multiply Tricks

Hi, welcome to nrrbeassistance.blogspot.comMental Maths Using Squares to Help Multiply Tricks and Shortcuts for the jobs, bank exams like RBI / SBI / IBPS CWE / RRB. Useful in the preparation of quantitative aptitude &/ numerical ability for the pupil preparing probationary officers (PO) / specialist officer (SO) / manager / assistants / clerks posts and others.

Mental Maths using Squares to help Multiply Tricks and Shortcuts

Two Numbers that Differ by 1
If a > b then a x b = a2 – a 
Ex.: 35 x 34 = 1225 – 35 = 1190
If a < b then a x b = a2 + a 
Ex.: 35 x 36 = 1225 + 35 = 1260

Two Numbers that Differ by 2
a x b = [(a + b)/2]2 -1 
Ex.: 26 x 28 = 272 -1 = 729 – 1 = 728

Two Numbers that Differ by 3 (a < b)
a x b = (a + 1)2 + (a – 1) 
Ex.: 26 x 29 = 272 + 25 = 729 + 25 = 754

Two Numbers that Differ by 4
a x b = [(a + b)/2]2 – 4 
Ex.: 64 x 68 = 662 – 4 = 4356 - 4 = 4352

Two Numbers that Differ by 6
a x b = [(a + b)/2]2 – 9 
Ex.: 51 x 57 = 542 – 9 = 2916 – 9 = 2907
Two Numbers that Differ by an Even Number: a < b and c = (b – a)/2
a x b = [(a + b)/2]2 – c2 
Ex.: 59 x 67 = 632 – 42 = 3969 – 16 = 3953

Two Numbers that Differ by an Odd Number: a < b and c = [1 + (b – a)]/2
a x b = (a + c)2 – [b + (c –1)2
Ex.: 79 x 92 = 862 – (92 + 36) = 7396 – 128 = 7268


Alerts: Dear viewer, “Hard work never fails”. Along with hard work include smart work for your goal. Your hard work and our smart work, guarantee success. To get in touch with you, we have created a WhatsApp Group named “Aptitude Study Materials”. Kindly send a message to +91-7893356131 as “add to Aptitude Study Materials" to add you to this group.

Updates: Don’t miss, what you want? So kindly, 1. Like our Facebook, 2. Subscribe by E-mail, 3. Follow our Google+, 4. Twitter 5. YouTube, 6. Download our Toolbar, 7. Install our App and 8. Others.

Help: If you have any suggestions, requests and problems, please comment below or ask us here.

Encourage us: Please don’t forget to G+1 and/ Like and/ Share and/ Recommend… thank you and all the best / best of luck for your bright future.

Our motto: Serve poor and needy whole heartedly – Nareddula Rajeev Reddy (NRR) and his team.

Comments

Popular posts from this blog

Top Numerical Reasoning Questions and Answers

S.CHAND: English Grammar Composition E-Book PDF Free Download; (Student's Exercises - Activities)

Mahendra's Reasoning Ability Study Material PDF for banking (RBI, SBI, IBPS: PO, SO, Clerks), Railway RRB and other Competitive Examinations