Answer:
The sum of a number, 1/6 of that number, 2 1/2 of that number, and 7 is 12 1/2. Find the number?
the number is 2.409
Step-by-step explanation:
based on the question; 
let the  number  N
1/6 of N = (1/6)N
21/2  of N = ( 5/2)N
now, the sum of  a number (N)  1/6 of that number(1/6)N , (5/2)N and 7  will be expressed as
N + ( 1/6)N + (5/2)N + 7 = 12 1/2
N + N/6 + 5N/2 + 7 = 25/2
find the lcm of the equation
we have;
(6N + N +15N + 42)/6= 25/2
(22N + 42)/6 = 25/2
Using cross multiplication we have
44N + 84 =  150
Collecting the like terms
44N = 150- 84
44N = 106
Divide both sides by 44
44N/44= 106/44
N = 2.409
 
        
             
        
        
        
Answer:
13
Step-by-step explanation:
 
        
                    
             
        
        
        
<span>In order to add and subtract fractions, we must be able to find a <u>common denominator</u>. 
The LCD, or least common denominator, is the LCM of the denominators. Once we've added, subtracted or multiplied fractions, we often have to simplify the fraction. 
In order to do this, we divide the numerator and denominator by their GCF. This means we must be able to find the LCM and GCF in order to work with fractions.</span>
        
                    
             
        
        
        
Answer:
8.6 × 10^5
Step-by-step explanation:
New Jersey 8th graders = 920,000
Rhode island 8th graders = 60,000
Difference in Rhode island 8th graders and New Jersey 8th graders population 
= 920,000 - 60,000
= 860,000
Answer in scientific notation
860,000
The decimal point will move 5 places in
= 8.6 × 10^5