Thank you for the opportunity to help you with your question!
a. sum s=n/2*(2a+(n-1)*d), here a=6, d=3. now, 444=a+(n-1)*d, so n=(444-6)/3+1=147.
hence sum, s=147/2*(12+(147-1)*3)=33075
b. sum s=4*127*(127+1)/2-11*127=31115
Content will be erased after question is completed.
Enter the email address associated with your account, and we will email you a link to reset your password.
Forgot your password?