up to = less than or equal to
at least = greater than or equal to
The answer is correct
the max weight shall be 80
mass of small box = 5 lb. ( and there are x number of boxes )
Mass of big box = 12 lb. ( and there are y number of boxes )
adding them up shall be less than or equal to 80 ( as the shelf can withstand up to 80 lbs. )
And the minimum number of boxes shall be equal to 4
If we take the x as the number of boxes, then x would be greater than or equal to 4
Hope my answer helps!
The formula for calculating the simple interest is given by
Here, P = Principle amount
r = annual interest rate in decimal
t = time in years.
Now, if we invest for months or week then in order to find the simple interest, we must convert the units in years.
Therefore, d is the correct option.
d) Interest rates are annual, so you must convert the units into years.
The denominator of 4 and 6 is ... (LCM) = 24
4,8,12,16,20,24
6,12,18,24
-4sqrt(x)-3 = 12 -> sqrt(x) - 3 = -3 -> sqrt(x) = 0
so x = 0, only solution, no extraneous solution
