Answer:
or 
Step-by-step explanation:
For this exercise you can convert the mixed number to an improper fraction:
1. Multiply the whole number part by the denominator of the fraction.
2. Add the product obtained and the numerator of the fraction (This will be the new numerator).
3. The denominator does not change.
Then:

You know that he had 30 minutes in time-out, he counted spots on the ceiling for
minutes and the rest of the time he made faces at his stuffed tiger.
Then, in order to calculate the time Calvin spent making faces at his stuffed tiger, you need to subract 30 minutes and
minutes:
or 
Answer: Due to its anonymous nature, if you lose your cash, it's gone. Payment cards can be cancelled and replaced swiftly and remotely. Whilst cash may offer you complete anonymity from data thieves, EMV chip enabled cards offer a more thorough form of payment authentication, providing an extra layer of payment security
So, therefore, C.
Answer:
9 + 10 = 21
Step-by-step explanation:
9 + 10 = 21
Factor out 9 and 10
9 = 3 · 3 10 = 2 · 5
Next multiply 3 by 2
3 × 2 = 6
Then multiply 3 by 5
3 · 5 = 15
Finally add the products
15 + 6 = 21
Hi there! The answer is 10.

We can use PEMDAS (Parenthesis, exponents, multiply, divide, add, subtract) to find our answer.
Since we cannot work inside the parenthesis in this question and since we don't have exponents, we can move on to multiplying.

Our next step would be subtracting. To make the process of subtracting some easier, I'll first change the fraction into a decimal.

Finally subtract.

The answer is 10.
~ Hope this helps you!