There would be 36 students at the end of the year
So walked 4/5 mile in a 4/9 h so just use the rule of 3 simple
60 minutes ------ 1 hour
x min. ----------- 4/9 h
--------------------------------
x = 4/9 *60/1 = 240/9 = 26,6 min.
4/5 mile -------in 26,6 min.
1 mile -------- x min.
-----------------------------
x = 1*26,6/(4/5) = 26,6 /(0,8) = 33,25 min.
1 mile ..... 33,25 min.
x miles ----- 60 min.
---------------------------
x = 60/33,25 = 1,8 miles
so their unit rate in miles per hour will be 1,8 miles / hour
hope this will help you
first one
Step-by-step explanation:
Answer:
It takes 27 minutes for the element to decay to 35 grams
Step-by-step explanation:
Given:
Initial amount = 790 grams
Final amount = 35 grams
Half life = 6 minutes
To find:
Time taken for the element to reduce into 35 grams = ?
Solutions
Time taken = 
On substituting the values given, Time taken
= 
= 
= 
= 26.97
= 27 minutes
