Mary has $65,000 to invest into two accounts. The first account is a private savings offering 6% annual interest and the second account is a government savings account offering 4% annual interest. How much money should Mary invest in each account to make $3,520 in total interest.

Step-by-step explanation:

Formula for calculating interest is expressed as;

I = PRT/100

P is principal

R is the rate

T is the time

For first account

I = P(1)(6)/100

I1 = 0.06P1

For the second bank!

I2 =>P2(1)(4)/100

I2 = 0.04P2

If the total interest is $3520, then

I1+I2 = 3520

0.06P1+0.04P2 = 3520 1

If the Amount invested = $65000

P1+P2 =65000 2

Solve. 1 and 2 simultaneously

Eqn 2 × 0.06

0.06P1+0.06P2 = 3900 3

Subtract 1 from 3;

0.04P2-0.06P2 = 3520-3900

-0.02P2 = -380

P2 = 380/0.02

P2 = $19000

Get p1;

P1 = 65000-P2

P1 = 65000-19000

P1 = $46000

Hence $46000 was invested in the first account and $19000 in the second

the population of other specie of birds will decline or other specie of birds will find some alternate source of food to survive.

explanation:

according to the competitive exclusion principle, which is also known as gause's law, two specie living in the same niche and feeding on the same resource cannot co-exist stably.

as we have well studied the theory of natural selection which states that only those organisms survive which have better tendency to compete for food and adapt to the environmental conditions.

coming towards the question, what wi ll happen when one species outcompetes the other for the small fish , the other specie will not get enough food and will start to die or decline in population. eventually either other specie needs to find another alternative food source for itself or migrate at some other location where there is less competition otherwise it will just not exist anymore at that niche.

hope it !