Step-by-step explanation:
x= Number of small pages
y= Number of full pages
1 x + 1 y = 21 .............1
Total words
1200 x + 1500 y = 27000 .............2
Eliminate y
multiply (1)by -1500
Multiply (2) by 1
-1500 x -1500 y = -31500
1200 x + 1500 y = 27000
Add the two equations
-300 x = -4500
/ -300
x = 15
plug value of x in (1)
1 x + 1 y = 21
15 + y = 21
y = 21 -15
y = 6
y = 6
x= 15 Number of small pages
y= 6 Number of full pages