It say estimate each problem to check if the students answer is reasonable. If not , Cross out the answer and write the correct answer. Show Your Work

It say estimate each problem to check if the students answer is reasonable If not Cross out the answer and write the correct answer Show Your Work class=

Respuesta :

2) [tex]-3\frac{1}{6} + 6\frac{2}{3}[/tex]        :   given answer  [tex]-3\frac{1}{2}[/tex]  is incorrect

Step by step explanation:

Step 1:

Split the question as,

[tex]-3 - \frac{1}{6} + 6 + \frac{2}{3}[/tex]

Step 2:

Add whole number and fractions individually, it becomes

[tex]6 - 3 + \frac{2}{3} - \frac{1}{6}[/tex]

= [tex]3 + \frac{12}{18} - \frac{3}{18}[/tex]

=[tex]3+\frac{1}{2}[/tex]  

can be written as  [tex]3\frac{1}{2}[/tex] (correct answer)

3)  -4.2 - (-2.9)    :  given answer - 1.3 is correct

calculated as

- 4.2 + 2.9 = - 1.3

4) [tex]3\frac{1}{5} - 2\frac{1}{2} + 2\frac{3}{5}[/tex]   :  given answer [tex]-3\frac{1}{3}[/tex] is incorrect

Step by step explanation:

Step 1:

Split the question as,

[tex]3 + \frac{1}{5} - 2 - \frac{1}{2} + 2 +\frac{3}{5} \\[/tex]

Step 2:

Add whole number and fractions individually, it becomes

[tex]3 + \frac{3}{5} +\frac{1}{5}- \frac{1}{2}[/tex]

= [tex]3 + \frac{4}{5} - \frac{1}{2}[/tex]

= [tex]3 + \frac{8}{10} - \frac{5}{10}[/tex]

= [tex]3 + \frac{3}{10}[/tex]

can be written as [tex]3\frac{3}{10}[/tex]      (correct answer)