The first thing we must do for this case is to define variables.
We have then:
x = Tim's age
Now we write the equation:
x + 7 = 3 (x-19)
Answer:
Tim's age in 7 years will be three times what it was 19 years ago:
x + 7 = 3 (x-19)
Answer:
increase = 37.38 cm²
You'd like the first way because it took less effort and less chance of a miscalculation.
Step-by-step explanation:
first way:
(just work with the difference in height)
(0.7 x 8.7 x 2) + (0.7 x 18 x 2) = 37.38 cm²
second way:
old total lateral surface area = (31 x 8.7 x 2) + (31 x 18 x 2) = 1655.4
new total lateral surface area = (31.7 x 8.7 x 2) + (31.7 x 18 x 2) = 1692.78
increase = 1692.78 - 1655.4 = 37.38 cm²
52-13=39
39/52x100=75
The percent of markdown: 75%
The problem deals with fractions comparison, lets do it:
21/30 > 2/3
we begin solving:
21 > (2/3)*30
21 > 2*10
<span>21 > 20
</span>therefore the proposed inequality is true, <span>21/30 > 2/3
You can solve as well getting same denominator for both fractions and comparing directly, in this case we need to get 2/3 to be divided by 30:
2/3 = (10/10)(2/3) = 20/30
So we have:
</span><span>21/30 > 2/3
</span>which is equal to:
<span>21/30 > 20/30
</span>and we compare directly because both fractions are divided by the same number, and we can see that the inequality is true.
