Answer:Mark Is 9 years old; Christine is 5 years old
Step-by-step explanation:
Present age
LET mark age be x
Christine be x-4 yrs
In 3 yrs Time
Mark will be x+3 yrs old
Christine will be (x -4 +3) = x-1 years old
Also, In 3 years time
Christine = 2/3 Mark
such that
x-1 = 2/3(x+3)
x -1= 2x+6 / 3
3x -3= 2x+6
3X--2X = 6+3
=X=9
Mark Is 9 years old
Christine is x -4 = 9-4=5 years old
Answer:40 - 4x >= 10 or x <= 7.5
Step-by-step explanation: hope this helps
Answer:
See Below
Step-by-step explanation:
x(2x) - 4(2x) + x(3) - 4(3)
= 2x² - 8x + 3x -12
= 2x²-5x-12
Answer:
José has 49 used stamps
Step-by-step explanation:
7 used stamps for every 4 new stamps
To solve this type of problem, we can use a ratio
7 : 4 ratio
He has 28 new stamps
7 : 4 = x : 28
Ratios can be written as fractions
Cross multiply
4x = 7(28) = 196
Divide by 4 on both sides
x = 49
Hope this helps :)
Answer:
yes it is a 75% decrease
Step-by-step explanation:
since 80-20=60
60/80=6/8=3/4
3/4=75%
