Assuming that the diagram on top is part of number 44, all you have to do is add the sides to get the sum. There are two lines that look like dashes. Those two lines mean that the triangle is isosceles or has two congruent sides. So, there are two 21 mm sides and one 12 mm side. If you add all those together (21 + 21 + 12), you'll get the sum of 54 mm. So your answer for number 44 is B.
45) The area of a rectangle is length × width. Multiply the length, 13, by the width, 8, and you'll get 104. Your answer is D.
46) Simply add the two numbers. However, since you're adding decimals together, make sure you line up the decimals points :
7.860
+ 0.785
——————
8.645
So, your answer for this problem is D.
47) Same concept as adding with decimals. Line up the decimals points :
7.124
— 0.986
——————
6.138
Your answer here is A.
48) Multiply the two numbers.
6.45
×. 3
——————
19.35
B is your answer.
49) 2.79 ÷ 3
Just divide as usual in this problem. 3 won't go into 2 at all, so you have to move on to the next number which is 7. Three goes into 27 nine times. And you have no remainder so move on to the next number. 3 goes into 9 three time so your answer should be 0.93 which is B.
50) This number is really really really easy I assure you!! So, it would not hurt to try it by yourself also!
Hint: the rounded number should be higher
