<span>4x+2y=10
x-y=13
x=13+y
4(13+y)+2y=10
52+4y+2y=10
52+6y=10
6y=-42
y=-7
x=13+y=13-7=6
</span>
Answer:
36 boys are at the camp
Step-by-step explanation:
complete question:
The sum of the digits of a two-digit numeral is 8. If the digits are reversed, the new number is 18 greater than the original number. How do you find the original numeral?
Answer:
The original number is 10a + b = 10 × 3 + 5 = 35
Step-by-step explanation:
Let
the number = ab
a occupies the tens place while b occupies the unit place. Therefore,
10a + b
The sum of the digits of two-digits numeral
a + b = 8..........(i)
If the digits are reversed. The reverse digit will be 10b + a. The new number is 18 greater than the original number.
Therefore,
10b + a = 18 + 10a + b
10b - b + a - 10a = 18
9b - 9a = 18
divide both sides by 9
b - a = 2...............(ii)
a + b = 8..........(i)
b - a = 2...............(ii)
b = 2 + a from equation (ii)
Insert the value of b in equation (i)
a + (2 + a) = 8
2a + 2 = 8
2a = 6
a = 6/2
a = 3
Insert the value of a in equation(ii)
b - 3 = 2
b = 2 + 3
b = 5
The original number is 10a + b = 10 × 3 + 5 = 35
We know that one inch has 16.5 turns.
To know the number of turns in 2.5 inches of thread, we will simply do a cross multiplication as follows:
number of turns = (2.5 x 16.5) / 1 = 41.25 turns
