Answer:
a) 910
b) 828100
c) 144320
Step-by-step explanation:
a. ∑y
This is the sum of all values of y. So

b. (∑y)^2
This is the square of the sum, so the square of 910, that we found in the previous item.
910² = 828100
c. ∑y^2
This is the sum of the squares of each amount spent. So

Answer:
21 + 3a
Step-by-step explanation:
3 (7+a)
distribute 3 into parentheses:
21 + 3a
Let us assume that the number of beige tiles bought by Susan = B
Number of red tiles bought by Susan = R
Number of navy-blue tiles bought by Susan =N
Number of tiles bought altogether = 435
Now from the given question we know:
Number of red tiles bought is 25 more than the number of beige tiles.
So
R = 25 + B
Number of navy blue tiles bought is 3 times that of the number of beige tile bought
So
N = 3B
We already know that the total number of tiles bought is 435
Hence
B + R + N = 435
B + (25 + B) + 3B = 435
5B + 25 = 435
5B = 435 -25
5B = 410
B = 82
R = 25 + B
= 25 + 82
= 107
N = 3B
= 3 * 82
= 246
So the number of Beige tiles bought by Susan = 82
The number of red tiles bought by Susan = 107
The number of navy-blue tiles bought by Susan = 246
6 trips because 1 trip = 3 km
If you divide 18 / 3 it would be 6 and by that multiply the # of trips.