Everyone works differently in mental meth.
To calculate 9*52, we note that 9=10-1, so mentally calculate
9(52)
=(10-1)(52)
=520-52 [ subtract 20 from each number]
=(520-20)-(52-20)
=500-32
=468.
Alternatively,
9*52=9*50+9*2=450+18=468
If you're good with multiplication and division,
9*52=3*3(52)=3*156=450+18=468
Gavin needs $80 to buy a fish tank. He has saved $8 and plans to work as a babysitter to earn $9 per hour. Which inequality shows the minimum number of hours, n, that Gavin should work as a babysitter to earn enough to buy the fish tank? 8 + 9n ≥ 80, so n ≥ 8 8 + 9n ≤ 80, so n ≤ 8 9n ≥ 80 + 8, so n ≥ 9.8 9n ≤ 80 + 8, so n ≤ 9.8
Answer:
(6)(2)+
(12)(2)
4
=18
Step-by-step explanation: