We at **ask-math **believe that educational material should be free for everyone. Please use the content of this website for in-depth understanding of the concepts. Additionally, we have created and posted videos on our youtube.

**We also offer One to One / Group Tutoring sessions / Homework help for Mathematics from Grade 4th to 12th for algebra, geometry, trigonometry, pre-calculus, and calculus for US, UK, Europe, South east Asia and UAE students.**

**Affiliations with Schools & Educational institutions are also welcome.**

Please reach out to us on [email protected] / Whatsapp +919998367796 / Skype id: anitagovilkar.abhijit

We will be happy to post videos as per your requirements also. Do write to us.

For finding rate of interest P. a , we use the formula of amount only.Where, A = amount

P = Principal

r = rate in percent

n = time in years.

1) At what rate percent P.a , compound interest will $ 10,000 amount to $ 13,310 in three years?

Here, P = $ 10,000 ; A = $ 13,310 ; n = 3 years

A = P ( 1 + r)

13,310 = 10,000( 1 + r )

13,310/10,000 = ( 1 + r )

1331/1000 = ( 1 + r)

( 11/10)

11/10 = 1 + r

11/10 – 1 = r

( 11 – 10)/10 = r

1/10 = r

As rate is in percent so, r = (1/10) x 100

Rate = 10 % P.a.

2) At what rate percent compound interest P.a. will $640 amount to $ 774.40 in 2 years ?

Here, P = $ 640 ; A = $ 774.40 ; n = 2 years

A = P ( 1 + r)

774.40 = 640 ( 1 + r )

774.40 /640 = ( 1 + r )

77440 /64000 = ( 1 + r)

( 88/80)

(11/10)

11/10 = 1 + r

11/10 – 1 = r

( 11 – 10)/10 = r

1/10 = r

As rate is in percent so, r = (1/10) x 100

Rate = 10 % P.a.

• Find Compound Interest when interest is compounded Half yearly

• Find Compound Interest when interest is compounded Quarterly

• Find CI when interest is compounded annually but Rates are different

• Finding Principal

• Finding Time Period of Investment

• Finding Rate of Interest

GMAT

GRE

1st Grade

2nd Grade

3rd Grade

4th Grade

5th Grade

6th Grade

7th grade math

8th grade math

9th grade math

10th grade math

11th grade math

12th grade math

Precalculus

Worksheets

Chapter wise Test

MCQ's

Math Dictionary

Graph Dictionary

Multiplicative tables

Math Teasers

NTSE

Chinese Numbers

CBSE Sample Papers