Answer:
Step-by-step explanation:
Let the age of a man = x
Age of his brother = y
Three yrs hence, a man will be three time his brother age
This is written as:
x + 3 = 3(y + 3)
x + 3 = 3y + 9 .... Equation 1
The sum of present age is 18
= x + y = 18
x = 18 - y
We substitute 18 - y for x in Equation 1
find their present age
18 - y + 3 = 3y + 9
Collect like terms
21 - 9 = 3y + y
12 = 4y
y = 12/4
y = 3 years
x = 18 - y
x = 18 - 3
x = 15 years
It’s 6
since it’s right at 5 & 7
Answer:
<em> (n - 1)/2</em>
Step-by-step explanation:
F = (1 - 1/n) + (1 - 2/n) + (1 - 3/n) + ...(1 - n/n)
= (1 + 1 ... + 1) - (1/n + 2/n + 3/n + ...n/n)
(there are n terms of 1)
= n - (1 + 2 + 3 + ... + n)/n
= n - [n x (n + 1)/2]/n
= n - [n x (n + 1)]/[2 x n]
= n - (n+1)/2
= (2n - n - 1)/2
= (n - 1)/2
Hope this helps!
Answer:
1. true 2. false 3. true 4. false
Step-by-step explanation:
6/10=18/20
no, there are 18 strawberry cups
6/10 is the same as 60% because it is 60/100
no, the correct answer is that 40% of the yogurt cups are not strawberry
Answer:
They sold 38 phone cases.
Step-by-step explanation:
The equation I used to solve is
