Perform the row operation: (2 -1 -4 7 0 -30 20 -50 0 30 24 6) --- (2 -1 -4 7 0 -30 -50 0 (blank) (blank) (blank))

Acollection of coins has value of 64 cents. there are two more nickels than dimes and three times as many pennies as dimes in this collection. how many of each kind of coin are in the collection?

Acampus club held a bake sale as a fund raiser, selling coffee, muffins, and bacon and eggs sandwiches. the club members charged $1 for a cup of coffee, 3$ for a muffin , and $4 for a back. and egg sandwich. they sold a total of 55 items , easing $119. of the club members sold 5 more muffins than cups of coffee, how many bacon and egg sandwiches he’s did they sell

240 seventh graders and two-thirds of the students participate in after-school activities how many students participate in after-school activities