The number=10x+y
we suggest this system of equations:
(10y+x)-(10x+y)=27
x+y=9 ⇒x=9-y
Can solve this system of equations by susbstitution method.
(10y+(9-y)-(10(9-y)+y)=27
10y+9-y-(90-10y+y)=27
10y-y+10y-y=27-9+90
18y=108
y=108/18
y=6
x=9-y
x=9-6
x=3
The number=10x+y=10(3)+6=36
Answer: the number is 36.
to check:
63-36=27
6+3=9
-x+y=3
y=x+3
2x + x + 3 =6
3x + 3 = 6
3x = 3
x = 1
-1 + y = 3
y = 4
2(1) + y = 6
2 + y = 6
y = 4
Solution: (1, 4)
Since no value is given to Eva, we'll call her x. Justin, then, is 7.50+x. That leaves Emma, who would be Justin (7.50+x) -12. If we add them all together we get 63. So our equation is
x + (7.50+x) + (7.50+x)-12 = 63
Combine like terms
x+x+x + 7.50+7.50-12 = 63
3x + 3 = 63
3x = 60
x = 20
Since we said Eva is x then Eva has 20 dollars.
Justin is 7.50 + x so 7.50+20=
$27.50
Emma is Justin - 12 so 27.50-12= $15.50
Let's check our answer...
15.50+27.50+20 = 63
63=63
It checks!
Answer:
8.15 miles
Step-by-step explanation:
Monday: 1 1/10 miles = 1.1
Multiply by 10 to get to 100
Wednesday: 4 4/5 miles = 4.8
Multiply by 20 to get to 100
Friday: 2 1/4 miles = 2.25
Multiply by 25 to get to 100
1.1 + 4.8 + 2.25 = 8.15 miles