14 + 28 + 42 + 56 + … 280
= 14 (1 + 2 + 3 + 4 + … + 20)
= 14 × 20 × 21 / 2
= 2940
where we use the well-known identity,
Target sells 24 bottles of water for $3.and 36 bottles of water for $4 Which is the better buy and by how much
2 answers:
You might be interested in
Width of the rectangle is 12 cm.
Solution:
The length of a rectangle is 4 cm more than its width , and the area of the rectangle is 96 cm². Find the width of the rectangle.
Given data:
Let x be width of the rectangle.
Length of the rectangle = (x + 4) cm
Area of the rectangle = 96 cm²
length × breadth = 96
Subtract 96 from both sides.
Let us factor the polynomial.
Take x common in 1st two terms and -12 common in next two terms.
Now, take (x + 8) common in both terms.
x + 8 = 0 and x - 12 = 0
x = -8 and x = 12
Dimension cannot be in negative terms, so ignore x = -8.
Width = 12 cm
Width of the rectangle is 12 cm.
Answer:
of fish in this aquarium are guppies.
Step-by-step explanation:
Let x be the number of guppies and y be the number of swordtails in the aquarium,
According to the question,
By cross multiplication,
Thus, the ratio of guppies and swordtail fishes is 8 : 9
Let guppies = 8x, swordtail = 9x
Where, x is any number,
Since, the aquarium contains only two kinds of fish, guppies and swordtails,
So, the total fishes = 8x + 9x = 17x
Hence, the fraction of fish in the aquarium are guppies =