Oldest = 2x
Middle = x + 5
Youngest = x
2x + x + 5 + x = 57
combine like terms
4x + 5 = 57
subtract 5 from both sides
4x = 52
divide both sides by 4 to isolate x
x = 13
Oldest = 2x = 2(13) = 26
Middle = x + 5 = 13 + 5 = 18
Youngest = x = 13
        
                    
             
        
        
        
Answer:
90 students.
Step-by-step explanation:
Given 1/4 of the 120 students took woodshop, just take the 3/4 that didn't take it:

Find common factors between 4 and 120 to simplify, so 4.

Now multiple across to get 90. 
 
        
             
        
        
        
The decimal equivalent of 1/4 is 0.25.
        
             
        
        
        
Answer:
D: A bond between two atoms
Step-by-step explanation:
 
        
             
        
        
        
Answer:
1.  P ( tails) = 1/2
2.P (number greater than 4)   = 1/3
3.  P (2 die sum to 8) = 5/36
Step-by-step explanation:
A coin only has 2 possibilities, head or tails, and they are equally likely
So the probability of getting a tails is 1/2 
P ( tails) = 1/2
A die has the numbers 1,2,3,4,5,6 .  There are 2 numbers greater than 4.  They are 5 and 6.  So there are 2 of the 6 choices that work.
P (number greater than 4)  = 2/6  = 1/3
See the dice chart
There are 36 possibilities when you roll the die. 
There are 5 that sum to 8
P (2 die sum to 8) = 5/36