Question 880917
a)
common ratio r=3
b)
Tn = T1 * r^(n - 1)
T7 = T1 * 3^(6)
T6 = T1 * 3^(5)
T7 +T6 =972

T1 * 3^(5)+ t * 3^(6)=972
T1*(3^5+3^6)=972
T1*243+729=972
T1*972=972
T1=1
S=T1*(1 - r^n)/(1 - r)
S=1*(1 - 3^6)/(1 - 3)
S=(1 - 3^6)/(1 - 3)
S=(1-729)/-2
S=-728/-2
S=364