How many pebbles did Gina collect?

Question

Taylor collected 3 times as many pebbles as Marco. Gina collected 21 fewer pebbles than Taylor. They collected 427 altogether. How many pebbles did Gina collect?

Answer 1

T = 3M

 

G = T - 21 = 3M-21

 

M + 3M + 3M - 21 = 427

 

7M - 21 = 427

 

7M = 448

 

M = 64

 

Marco has   64 marbles.

Taylor has 192 marbles.

Gina has   171 marbles.