Just rotate it 90 degrees clockwise like this
The general way to work this out is to solve the general expression for
the remaining quantity versus half-life, using logarithms. But that's not
necessary with these numbers.
Look at the numbers:
-- 3 mg is 1/4 of 12 mg.
-- 1/4 is the product of (1/2) x (1/2).
-- So the 3 mg is what's left of 12 mg after 2 half-lives.
The 26 minutes must be two half-lives.
-- The half-life of that substance is 26/2 = <em>13 minutes</em>.
Go Maggie !
3 rows of 12
9 rows of 4
2 rows of 18
6 rows of 6
Toby saves 30.30 money by buying 30 T-shirts at better price.
Step-by-step explanation:
Cost of pack of 5 T-shirts = 13.00 money.
Cost of pack of 2 T-shirts = 7.22 money.
Toby wants to buy total T-shirts = 30 T-shirts.
<u>Case 1 </u>:
For 30 T-shirts, If Toby buys in packs of 5 T-shirts then the number of packs he should buy = 30/5 = 6 packs.
The cost for six packs of 5 T-shirts = 6*13.00 = 78.00 money.
<u>Case 2 </u>:
For 30 T-shirts, If Toby buys in packs of 2 T-shirts then the number of packs he should buy = 30/2 = 15 packs.
The cost for 15 packs of 2 T-shirts = 15*7.22 = 108.30 money.
The money saved = 108.30 -78.00 = 30.30 money.
Therefore, The better price to buy 30 T-shirts is 78.00 money.
