30%
percent means parts out of 100 so 30%=30/100=3/10
42 is 3/10 of x
'of' can be translated to multiply
42=3/10 times x
multiply both sides by 10/3 to get rid of fraction
420/3=x
140=x
the number is 140
Answer:

Step-by-step explanation:
Isolate the variable by dividing each side by factors that dont't contain the variable.



-8 -8

Divide both sides by 5.

ellen had 44 per box and carl had 36 per box
but if they had only two boxes altogether then each box had 80 cans in it
The third side or c is 8 < third side [c] < 12
Add like terms
only add x's together
2x+3x=5x
we can't add x's and numbres so
answer is 5x+4