Two proverbs

1. It goes without saying that many hands make light work. 

it goes without saying that ... 不言而喻

many hands make light work     众人拾柴火焰高/人多无重活

light     轻的/重量轻的

2. It goes without saying that a penny saved is a penny earned. 

penny    一便士

save    省下/攒/节约

earn     赚取

a penny saved is a penny earned     省一分钱是一分钱