Question

Linda saves N$ 150 the first month and every month later N$ 15 more.Anil starts with the same amount but increses it by 5% each month later.who will have more after 3 and a half years and how much more?

Answer 1

Given :

The amount of money saves by Linda in first month = $ 150

The amount of money saved by Linda in later months = $ 15 more

And

Anil saves money at first month = $ 150

The rate of increasing saving = r = 5% each months

To Find :

who will have more after 3 and a half years and by how much more

Solution :

Total number of months =  12 × 3 + 6 = 42

The money saves by Linda = $ 150 + $ 15 × 41

                                            =  $ 150 + $ 615

                                            = $ 765

Again

For Anil

The money saves by Anil = First month money + money saves after n years

The money saves by Anil = $ 150 + $ 150 × $(1+\dfrac{rate}{12\times 100})^{12\times time}$

                                           = $ 150 + $ 150 × $(1+\dfrac{5}{12\times 100})^{12\times 41}$

                                           = $ 150 + $ 150 × $(1.00416)^{492}$

                                           = $ 150 + $ 1160

                                           = $ 1310

∵ The money saves by Linda = $ 765

And The money saves by Anil = $ 1310

∴ The money saves by Anil is more than that of Linda = $ 1310 - $ 765

                                                                                         = $ 545

Hence, The money saved by Anil is more that that of Lind and by $ 545  Answer