Let t represent Todd's age now.
.. 4(t -3) -(t -3) = 81 . . . . . . 3 years ago, their differnce in ages was 81.
.. 3t -9 = 81
.. t = (81 +9)/3 = 30
Todd is 30 now.
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You can also work this by considering "ratio units." 3 years ago, the ratio of their ages was 4:1, a difference of 3. That difference corresponds to 81 years, so each "ratio unit" represents 81/3 = 27 years. Todd's age then was 1 ratio unit, 27 years. Now, Todd's age is 30.
Answer:
<em>550 </em><em>students are in the school.</em>
Step-by-step explanation:
The way I found my answer was by first turning<em> 74% into a decimal</em>, which is <em>0.74</em>. Then I <em>divided 407 </em>by<em> 0.74</em> and I got<em> 550</em>. Therefore, <em>550 is our answer.</em>
Answer: b
Step-by-step explanation:
For find f(-2) of f(x)=7x+3, plug in -2 for x.
7(-2)+3=y
-14+3=y
y=-11
To find the rate, or the slope, you divide x/y. So 2/6 is 1/3. 3 over 9 is also 1/3. So the rate is 1/3. In rates you always divide, you don't mulitply or subtract or add to find the rate.