Question

a manufacturer of wire produced 1400 M wire in the 50 year and 1600 m in the 9th year assuming that the production increases uniformly by a fixed number every year find the production in the 12th here and in which year the production with in 1900 m and total production in 9 years
pls tell me the answerrr plsssss
class 10 - chapter 5​

Answer 1

Step-by-step explanation:

It is in arithmetic progression.

t5 = a +(5-1)d=1400

t9 = a +(9-1)d = 1600

solving 4d = 200

=> d = 50

so, a = 1200

t12= 1200+ 11*50 = 1750

tn=1900 => 1200+(n-1)50 = 1900

=>n = 15

On 15th year the production will be 1900m

S9 = 9/2{1st term + 9th term} gives total production in 9 years