Answer:
A simple way to mentally subtract is to simplify the numbers, subtract, then subtract or add for the simplified answer.
Step-by-step explanation:
A simple way to mentally subtract is to simplify the numbers, subtract, then subtract or add for the simplified answer. For this 304 - 81 is easier as 300 - 80. Make note that we took away 4 from 304 and 1 from 81. Now we just subtract mentally, and 300 - 80 = 220. If we took 4 from 304, this means that our answer should be 4 less, since 4 less would be 304 - 80 = 216. If we took 1 from 81, then we add 1 back to get the equation 304 - 81 = 217.
304 - 81 = ?
300 - 80 = 220
304 - 80 = 216
304 - 81 = 217
Answer:
x = 10
Step-by-step explanation:
Using the rules of logarithms
• log x + log y ⇔ log(xy)
• log
⇔ n log x
• log x = log y ⇒ x = y
Given
ln20 + ln5 = 2 lnx , then
ln(20 × 5) = ln
ln 100 = ln
, hence
x² = 100 ( take the square root of both sides )
x = 10
There are 3 even numbers: 2,4,6. If you add 3 there is 4. There is 6 possible outcomes 1,2,3,4,5,6. So the probability is 4/6, 2/3, 66.666....% or 0.6666666....
7(3a + 12) = 168 ← ( divide both sides by 7 )
3a + 12 = 24 ← ( subtract 12 from both sides )
3a = 12 ← ( divide both sides by 3 )
a = 4
OR
distribute the parenthesis by 7
21a + 84 = 168 ← ( subtract 84 from both sides )
21a = 84 ← ( divide both sides by 21 )
a = 4