we are given
initial amount =1800
so,
P=1800
doubles in value every 7 years
so, we can find function
[tex] A=P(2)^{\frac{t}{7} } [/tex]
now, we can plug P=1800
[tex] A=1800(2)^{\frac{t}{7} } [/tex]
now, we can plug t=42
[tex] A=1800(2)^{\frac{42}{7} } [/tex]
[tex] A=115200 [/tex].............Answer
