Answer:
its E 21
Step-by-step explanation:
The answer Its 4.5281 ....etc
Answer:
4,8,12 hope that helps heeeeheheʘ‿ʘ
Answer:
4.58
Step-by-step explanation:
21 is not a perfect square, but lies between the perfect squares 16 and 25. Thus, √21 lies between √16 and √25, that is, between 4 and 5. Since 21 is closer to 25 than to 16, √21 is closer to 5 than to 4. A rough estimate of √21 would be 4.7.
√21 done on a calculator comes out to 4.58.
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.
