1) After giving $5 to Greg, David has $25. Greg now has 1/5 as much as Davis does. How much did Greg start with?
Now David has $25
Greg now has 1/5 of David, or 1/5 of 25, or 5.
So before he got $5 from David, Greg had 5-5=0, or nothing.
2) if 3a+4b=4a-4b=21 find the value of a
A.
3a+4b=4a-4b
=>
8b=a...........(1)
B.
4a-4b=21
=>
4(8b)-4b=21 substitute (1)
=>
28b=21
=>
b=3/4
so
a=8b=8(3/4)=6
3) If N is a positive integer, which of the following does not have to be a divisor of the sum of N,6N, and 9N?
Sum = N+6N+9N = 16N
So any of the factors of 16 will divide the sum, namely 1,2,4,8,16 will all divide the sum. Any other number will not divide the sum as long as N is not a multiple of that number, i.e. another number does not have to be a divisor of the sum.
1) After giving $5 to Greg, David has $25. Greg now has 1/5 as much as Davis does. How much did Greg start with?
2) if 3a+4b=4a-4b=21 find the value of a
A)3
B)6
C)21
D)42
E) the answer can not be determined from the information given
^ i think it’s C?
3) If N is a positive integer, which of the following does not have to be a divisor of the sum of N,6N, and 9N?
A)
B)2
C)4
D)9
E)16
^Is it D??
1 answer
2 answers