Answer:
The even numbers between 0 and X represents an arithmetic sequence with a common difference of 2
The rule of arithmetic sequence = a + d(n - 1)
Where a is the first term and n is the number of terms
So, for the even numbers between 0 and X
The first term = a = 0
d = 2
So, we need to find n at the last term which is X
∴ X = 0 + 2 ( n -1 )
∴ n - 1 = X/2
∴ n = X/2 + 1
The sum of the arithmetic sequence = (n/2) × (2a + (n−1)d)
Substitute with a and d and X
So, the sum = (n/2) * (2*0 + (n−1)*2)
= (n/2) * ((n−1)*2)
= n(n-1)
= (X/2 + 1) * (X/2)
= X/2 by (X/2 + 1)
So, The quick way to add all even numbers between 0 and X always works.
Answer:
If cookies are for $1 and brownies are for $2, let number of cookies = x and number of brownies = y
∴ $1*(x*1) + $2*(y*1) = $13
Step-by-step explanation:
1) You can buy 4 brownies for $2 each = 2*4 = $8
The rest you can buy cookies = 5 cookies = $5
$8+$5=$13
2) You can buy 5 brownies and 3 cookies = $10+$3 = $13
3) You can buy 3 brownies and 7 cookies = $6+$7=$13
Equation: -
If cookies are for $1 and brownies are for $2, let number of cookies = x and number of brownies = y
∴ $1*(x*1) + $2*(y*1) = $13
Answer:
Yes, distance in yards can be obtained by multiplication.
Step-by-step explanation:
Given that the distance between tow points is 90 feets, The distance between these two points in yards can be obtained either by multiplication or division.
I foot = 0.3333 yards
To convert distance between the second and third bases from feet to yard ;
Multiply distance in feets by 0.3333 to obtain the corresponding distance in yards ;
90 * 0.3333 = 29.997 = 30 yards
Answer:
243 divided by 3 equals 81 so r=81
Step-by-step explanation:
