Need to understand n resolve this math problems 4(1/4+1/5)+4

What is r i 4.5+10r=-6.5 with work pls

Afactory buys 10% of its components from suppliers b and the rest from supplier c. it is known that 6% of the components it buys are faulty. of the components brought from suppliers a,9% are faulty and of the components bought from suppliers b, 3% are faulty. find the percentage of components bought from supplier c that are faulty.

Which function represents the sequence? f(n)=n+3 f(n)=7n−4 f(n)=3n+7 f(n)=n+7