She earns 20 dollars as a carpenter and 25 dollars as a blacksmith
b+c=30 hours since she works 30 hours a week
25b+20c=690 since she earns 690 dollar totally and earns 25 dollars an hour as a blacksmith and 20 dollars an hour as a carpenter
lets multiply b+c=30 by -20
-20b-20c=-600
if we substract that from
25b+20c=690
5b=90
b=18 she worked as a blacksmith for 18 hours
No 13.3813 + 0.1100 = 13.4913. (max. standard deviation)
13.4813 is less than max. standard deviation
I guess that is 1:10
Hope ur help !;(
Answer:
Step-by-step explanation:
<u>Ratio of turns</u>
<u>If A = 60 then the ratio is</u>
- 60/B = 2/3 ⇒ B = 60*3/2 = 90
