20 because if you take 20 half it that would be 10 then take away 4 that would then equal 6.
For the first question, the total is 240 so that goes in front of the equals sign. he has already worked 97 hours, so the expression on the right begins with 97 and adds the unknown number of hours, <em>h</em>, to it:
240 = 97 + <em /><em>h</em>
For the second question, there is no graph so I cannot answer it.
3rd question: no image, can't answer.
4th question:
Use a factor tree:
240
/ \
10*24
/\ /\
5*2 *8*3
/ / /\ \
5 * 2 *4*2 *3
/ / /\ \ \
5 * 2 *2*2 * 2 * 3
Starting with the smallest factor and using exponents we have
27. -24 is the answer
29. -18 is the answer