Question #8994e

3 Answers
Jan 13, 2018

=K68.25
=K3.25

Explanation:

This can be solved using the formula:
I="Pi"n
where:
I="Interest"
P="Principal"
i="interest rate"
n="no. of years"

Plug in data provided to find the Interest (I) after after 3 years .
I="Pin"
I=K650xx(0.035)/(cancel(yr))xx3cancel(yr)
I=K68.25

Thus, the interest (I) per year is K22.75

If the interest rate is increased by 3.75% after the first year; the Interest (I) earned for the remaining 2 years can be computed as;
I="Pin"
I=K650xx(0.0375)/(cancel(yr))xx2cancel(yr)
I=K48.75

Thus, the total Interest earned before and after the increase can be computed as shown;
I_(t)=I_(fy)+I_(s&ty)
I_(t)=K22.75+K48.75
I_(t)=K71.50

Therefore, an increase of the Interest earned is
=I_(3.50&3.75%)-I_(3.50%)
=K71.50-L68.25
=K3.25

Jan 13, 2018

(a) Interest earned after 3 years @ 3.5% Interest = color(purple)(K 68.25)

(b) Increase in Interest due to rise in interest to 3.75% after one year = color(green)(71.5 - 68.25 = K 3.25)

Explanation:

I = (P N R) / 100

Where I = Simple Interest earned, P = Principal, N = No. of years & R = Rate of Interest in percentage.

(a) Given P = K 560, N = 3 years, R = 3.5%

I = ( 650 * 3 * 3.5) / 100 =color(red)( K 68.25)

(b) New Rate of Interest R_1 = 3.75% & N_1 = 2 years

Interest earned I_1 = (650 * 2 * 3.75) / 100 = color(blue)(K 48.75)

Old rate of interest R = 3.5%, Period N_1 = 1 year

I_o = (650 * 3.5 * 1) / 100 = color (blue)(22.75)

Total Interest = 48.75 + 22.75 = K 71.5#

Increase in interest with the revised interest rate after 1 year color(green)(I_i = 71.5 - 68.25 = K 3.25)

Jan 13, 2018

"Part a: "K68.25

"Part b: "K3.25

Explanation:

color(blue)("Preamble")

The symbol % cab be thought of as representing a fraction but one that is worth 1/100. So we have:

3.5% ->3.5xx% ->3.5xx1/100=3.5/100

A direct comparison is the the metric measure of centimetres. The part word centi signifies 1/100. So we have 1/100xx1" metre"

It is usual to translate the word of (as in 1/100 of 1 metre) to mean multiply. So 3.5% of 'something' is stating 3.5%xx"'something'"

The wording 'per anum'-> 'per' means for each of 1 and 'anum' means 'year'. So 'peranum' is stating 'for 1 year'
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
color(blue)("Answering the question")

color(brown)(ul("For EACH year we have:"))" simple interest"

3.5%" of "K650 color(white)("d") -> color(white)("d") 3.5/100xxK650 = color(cadetblue)(K22.75) color(red)(larr"Checked")

3.75%" of "K650 color(white)("d") ->color(white)("d") 3.75/100xxK650= color(sienna)(K24.375) color(red)(larr"Checked")

..............................................................
color(brown)("Question part a")" 3 years at 3.5%"

"3 years at 3.5% is: "3xxcolor(cadetblue)(K22.75) = K68.25 color(red)(larr" Corrected"

.............................................................
color(brown)("Question part b")
Interest starts at 3.5% but at the end of the first year it is changed to 3.75%

1 year at color(white)(.)3.5% color(white)("d") = color(white)("d") 1xx color(cadetblue)(K22.750)color(white)(d)=color(cadetblue)(Kcolor(white)(.)22.75)
2 years at 3.75%=color(white)("d")2xxcolor(sienna)(K24.375)=ul(Kcolor(white)(".")48.75larr" Add")
color(white)("ddddddddddddddddddddddddddddd")Kcolor(white)(".")71.50

So the increase in interest is:

Kcolor(white)(".")71.50
ul(Kcolor(white)(".")68.25 larr" Subtract")
Kcolor(white)(".")color(white)("d")3.25color(red)(larr" Corrected"