Answer:
Step-by-step explanation:
if the ratio is 8:11 then 40:x
Cross multiply
8 40
11 x
8x=440
And divide by 8
x=55. She has 55 books
Answer:
x <2
Step-by-step explanation:
2.5 – 1.2x < 6.5 – 3.2x
Add 3.2x to each side
2.5 – 1.2x+3.2x < 6.5 – 3.2x+3.2x
2.5 +2x < 6.5
Subtract 2.5 from each side
2.5+2x-2.5<6.5-2.5
2x<4
Divide by 2
2x/2 < 4/2
x <2
Answer:
Step-by-step explanation:
90x - 60y = 68.....multiply by -1
90x - 70y = 91
---------------------------
-90x + 60y = -68 (result of multiplying by -1)
90x - 70y = 91
---------------------------add
-10y = 23
y = -23/10 <===
90x - 60y = 68
90x - 60(-23/10) = 68
90x + 138 = 68
90x = 68 - 138
90x = - 70
x = -70/90
x = -7/9 <=====
Answer:
6 weeks
Step-by-step explanation:
Total savings= $325
For every week, his total savings decrease by $28.
Let's form an expression for the amount of money left in his account after w weeks.
325 -28w= 157
28w= 325 -157
28w= 168
<em>Divide by 28 on both sides:</em>
w= 168 ÷28
w= 6
Thus, there are 6 weeks until he has $157.