Answer:
the right answer is 18 and under for part a for part b the answer is 45 -64
Sove the system:
x: Mary´s age
y: Mom´s age:
x + y = 67
3x + 7 = y
Replace y in the first equation:
x + 3x + 7 = 67
4x = 67 - 7
4x = 60
x = 15 yrs.
y = 67 - 15 = 52 yrs
Step-by-step explanation:
if there is nothing missing, we have
x + 25/-8 = -6
in order to compare or add or subtract fractions, we need to bring them all to the same denominator (bottom part).
remember, integer numbers are fractions too. like here
-6 = -6/1
25/-8 = -25/8
so, how can we bring -6/1 to .../8 ?
by multiplying 1 by 8.
but we cannot multiply only the denominator by 8. otherwise we would suddenly have
-6/8
and is -6/8 = -6/1 ? no, certainly not.
to keep the original value of the fraction we have to do the same multiplication also with the numerator (top part).
so, we actually do
-6/1 × 8/8 = -48/8
with this little trick we have now .../8 to operate with, and our transformed fraction has still the same value
-6/1 = -48/8 indeed.
so, we have
x + -25/8 = -48/8
x - 25/8 = -48/8
x = -48/8 + 25/8 = -23/8
Hi
1 cm³ = 1 mL
315 cm³ = 315 mL
Answer: a)