Answer:
B= 13
Step-by-step explanation:
10x-5= 180-(4x+3)
10x-5=180-4x-3
10x-5+3=180-4x
14x-2=180
14x= 180+2
14x= 182
x=182/14
x=13
Try this:
1) note that weight of pure antifreeze before mixing and after mixing is the same. So, if 'x' is weight of pure antifreeze in 50% solution, it is possible to make up equation before mixing: 0.5x+0.2*90.
2) there are 0.2*90=18 gal. of pure antifreeze in the 20% solution. If 'x' gal. is the weight of pure antifreeze in 50% sol. and 18 gal. is the weight of pure antifreeze in 20% sol., it is possible to make up an equation after mixing: 0.4(x+18).
3) using the both parts: 0.5x+0.2*90=0.4(x+18) ⇒ x=54 gal. of <u>pure</u> weight.
4) to find 50% solution of 54 gal. pure weight just 54:0.5=108 gal.
Answer: 108 gal.
Answer:
4
Step-by-step explanation:
If each of 12 kids ate 1/3 of a pizza, the amount eaten was ...
12 × 1/3 pizza = 12/3 pizza = 4 pizza
Dominic needed to buy 4 pizzas.
Any unknown number in an equation you represent with a variable
