Answer:
6
Step-by-step explanation:
Hope this helps! Pls give brainliest!
Let,
digital cameras be "x"
video cameras be "y"
Now,
According to the question,
5x + 3y = $3,213..................................................equation (1)
y = 4x..................................................................equation (2)
Taking equation (1)
5x + 3y = $3,213
Substituting the value of "y" from equation (2), we get,
5x + 3(4x) = $3,213
5x + 12x = $3,213
17x = $3,213
x = $3,213 / 17
x = $189
Taking equation (2)
y = 4x
Substituting the value of "x", we get,
y = 4 ($189)
y = $756
Now,
John buys a digital and a video camera. So, it costs him ($189 + $756) = $945
The three numbers are 12, 18 and 24
Arithmetic progression
Let the 3 number in arithmetic progression be:
a-d, d, a+d ...
If their sum is 3, then;
a-d+d+a+d = 3
2a + d = 3 ........... 1
If the sum of their squares is 11, then;
(a-d)² + d² + (a+d)² = 11
a²-2ad+d²+d²+a²+2ad+d² 11
2a²+3d² = 11 ....... 2
Solving the equations simultaneously, d = 6 and a = 12
First-term = 12
second term = 18
Thirs term = 24
Hence the three numbers are 12, 18 and 24
Hope this helps you!!!!!! :D
5/12*6 =5/12*6/1 crosscancle you get 5/2 the you get 2 1/2