Mary deposits R400 every three months into a bank account earning interest at 16% per year, compounded quarterly. The approximate time that it will take Mary to save R40000 is

The approximate time that it will take Mary to save R40000 is 29 years

Step-by-step explanation:

A= p(1+r/n)^nt

t = log(A/P) / n[log(1 + r/n)]

A = R40000

n = 4

P = R400

r = 16%

t = log(A/P) / n[log(1 + r/n)]

= log(40,000 / 400) / 4{log(1+0.16/4)}

= log(100) / 4{log(1+0.04)}

= 2 / 4{log(1.04)}

= 2 / 4(0.0170)

= 2 / 0.068

= 29.41

t = 29.41 years

Approximately 29 years

The approximate time that it will take Mary to save R40000 is 29 years

infinitely many solutions

step-by-step explanation:

we have been given the equation;

2(2x + 3) = -4 + 2(2x + 5)

we need to determine the value of x.

2(2x + 3), we expand this expression to obtain 4x + 6

similarly 2(2x + 5) will become 4x + 10

now we have;

4x + 6 = -4 + 4x + 10

4x + 6 = 4x + 10 - 4

4x + 6 = 4x + 6

the expression on the left hand side is identical to the one on the right hand side. therefore, we are looking at just a single straight line whose equation is;

y = 4x + 6

consequently, we shall have infinitely many solutions

225x²+4=0

225x²=0-4

225x²=-4

x²=-4/225

x=±√-4/225