Answer:
The value of A is 5
Step-by-step explanation:
- The number is divisible by 3 if the sum of its digits is a number
divisible by 3
- Ex: 126 is divisible by 3 because the sum of its digits = 1 + 2 + 3 = 6
and 6 is divisible by 3
- The number is divisible by 5 if its ones digit is zero or 5
- Ex: 675 is divisible by 5 because its ones digit is 5
890 is divisible by 5 because its ones digit is 0
- We are looking for the value of A in the 4-digit number 3A5A which
makes the number divisible by both 3 and 5
∵ A is in the ones position
∴ A must be zero or 5
- Let us try A = 0
∵ A = 0
∴ The number is 3050
∵ The sum of the digits of the number = 3 + 0 + 5 + 0 = 8
∵ 8 is not divisible by 3
∴ 3050 is not divisible by both 3 and 5
∴ A can not be zero
- Let us try A = 5
∵ A = 5
∴ The number is 3555
∵ The sum of the digits of the number = 3 + 5 + 5 + 5 = 18
∵ 18 is divisible by 3
∴ 3555 is divisible by both 3 and 5
∴ A must be equal 5
* <em>The value of A is 5</em>
Answer:
<h3>The nth term
Tn = -8(-1/4)^(n-1) or Tn = 6(1/3)^(n-1) can be used to find all geometric sequences</h3>
Step-by-step explanation:
Let the first three terms be a/r, a, ar... where a is the first term and r is the common ratio of the geometric sequence.
If the sum of the first two term is 24, then a/r + a = 24...(1)
and the sum of the first three terms is 26.. then a/r+a+ar = 26...(2)
Substtituting equation 1 into 2 we have;
24+ar = 26
ar = 2
a = 2/r ...(3)
Substituting a = 2/r into equation 1 will give;
(2/r))/r+2/r = 24
2/r²+2/r = 24
(2+2r)/r² = 24
2+2r = 24r²
1+r = 12r²
12r²-r-1 = 0
12r²-4r+3r -1 = 0
4r(3r-1)+1(3r-1) = 0
(4r+1)(3r-1) = 0
r = -1/4 0r 1/3
Since a= 2/r then a = 2/(-1/4)or a = 2/(1/3)
a = -8 or 6
All the geometric sequence can be found by simply knowing the formula for heir nth term. nth term of a geometric sequence is expressed as
if r = -1/4 and a = -8
Tn = -8(-1/4)^(n-1)
if r = 1/3 and a = 6
Tn = 6(1/3)^(n-1)
The nth term of the sequence above can be used to find all the geometric sequence where n is the number of terms
Answer:
The area of cheese is 388π cm.
Step-by-step explanation:
Given that,
Radius of pizza = 20 cm
Number of pieces = 12
Radius of circle = 1 cm
We need to calculate the area of pizza
Using formula of area
Put the value into the formula
We need to calculate the area of circle
Using formula of area
Put the value into the formula
Now, we multiply the result by 12 because they are 12 salamis.
So. the area of salamis will be
We need to calculate the area of cheese
The total area of the pizza and subtract the area of the salamis
Put the value in to the formula
Hence, The area of cheese is 388π cm.
Answer:
D. 972 ft^2
Step-by-step explanation:
SA = 2B + PH
where SA = total surface area of the prism,
B = area of a base
P = perimeter of the base
H = height of the prism
SA = 2 * bh/2 + (15 ft + 12 ft + 9 ft)(24 ft)
SA = (9 ft)(12 ft) + (15 ft + 12 ft + 9 ft)(24 ft)
SA = 972 ft^2
