I am pretty positive that it is b...
Ok so first I am assuming you ment 2 sevenths so 12 divided by 2 sevenths is 42. so the father is currently 42. so when she was 10 he was 40. since 10 is 4 times 40 that is the age we need. so 42 minus 40 is 2. therefore the answer is 2.
Dave pays $15 and tax is $1.2 so dave spent a total of $16.20.
Mel pays $20 and tax is $1.6 so Mel spent a total of $21.60.
All you need to do is convert the percent to a decimal, so take 8 and divide by 100 and you get 0.08. then you need to multiply the cost by the tax so 15*0.08=1.2 then you just add tax to original amount 15+1.2=16.2
:)
Find the square root of 13, which is 3.6
The answer is $17.5.
How I did it-
All you need to do was multiply $3.50 x 5
