a debt of R 1000th with interest at 16% compounded quarterly,is to be amortised by 20 quarterly payments over the next five years. What will the size of these payments be

Where's the problem? Just plug your numbers into the formula, which I assume you have handy.

A = Pr(1+r)^n/((1+r)^n-1)
= 1000*0.16(1+.16/4)/((1+.16/4)^20-1)
= 139.70

i = .16/4 = .04

n = 5(4) = 20
PV = payment (1 - (1+i)^-n)/i

P( 1 - 1.04^-20)/.04 = 1000
P = .04(1000)/(1 - 1.04^-20)
= 73.58

Wow - I guess I mangled that one, eh?

perhaps "alternative facts" are even entering the world of math, lol, strange times

To calculate the size of the payments for amortizing a debt, we can use the formula for calculating the periodic payment for an amortizing loan:

Payment = Principal * (r * (1 + r)^n) / ((1 + r)^n - 1)

In this case, the principal is R 1000, the interest rate is 16% (or 0.16), and the loan will be amortized over 20 quarterly payments (5 years).

Step 1: Convert the annual interest rate to the quarterly interest rate.
Since the interest is compounded quarterly, we need to convert the annual interest rate to the quarterly rate. This can be done by dividing the annual rate by the number of compounding periods in a year.

Quarterly interest rate = Annual interest rate / Number of compounding periods per year
= 16% / 4
= 4%

Step 2: Convert the quarterly interest rate to a decimal.
To use the formula, we need to convert the quarterly interest rate from a percentage to a decimal.

Quarterly interest rate = 4% / 100
= 0.04

Step 3: Calculate the periodic payment.
Now, we can substitute the values into the formula to calculate the size of the payments.

Payment = R 1000 * (0.04 * (1 + 0.04)^20) / ((1 + 0.04)^20 - 1)

Using a calculator or spreadsheet software to evaluate the expression, the size of each payment turns out to be approximately R 93.22.