A bag contains purple marbles and white marbles, 42 in total. The number of purple
marbles is 7 more than 4 times the number of white marbles. How many purple
marbles are there?

35

Step-by-step explanation:

let x be the number of white marbles and y be the number of purple marbles

this implies that,

y = 42-x

also y = 7+4x

equate the two equations for y

42-x = 7+4x

collect like terms

42-7 = 4x +x

35 = 5x

divide both sides by the coefficient of x which is 5

35/5 = 5x/5

x = 7

substitute the value of x into the first equation

y = 42-x = 42- 7 = 35

there are 35 purple marbles.

1.30

step-by-step explanation: