Respuesta :

Given that:

Initial amount = $1400

Amount deposited per week = 50

Amount after 47 weeks =?

Using the Arithmetic Progression relation :

Tn = A + (n - 1)d

Weekly deposit = d = 50

A = initial / first deposit = 1400

n = number of deposits

T47 = 1400 + (47 - 1)50

T47 = 1400 + (46)*50

T47 = 1400 + 2300

T47 = 3700

She will have $3700 after 47 weeks.