Terezka 2

Terezka has two younger siblings, 40-month-old Anička and 7-month-old Kája.
o Calculate how many months it will take for Anička to be four times older than Kája.
o Calculate the age difference between Tereza and Anička if Tereza celebrated her sixth birthday four months ago. State the result in months.

Correct answer:

a =  4
b =  36 m

Step-by-step explanation:

$$\begin{gathered} A=40 \\ 40+a=4\cdot (7+a) \\ 3a=12 \\ a=\frac{12}{3}=4 \\ a=4 \end{gathered}$$

$$\begin{gathered} T=6\cdot 12+4=76\text{m} \\ b=T-A=76-40=36\text{m} \end{gathered}$$

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