Answer:
6
Step-by-step explanation:
Answer:
The average weight of new born otter was, 
Step-by-step explanation:
Let average weight of new born otter be x.
As per the given statement: At birth it's weight was 7/8 kilograms which is 9/10 kilogram less than the average weight of a new born otter in the aquarium
"
kg less than average weight of a new born otter" means 
As per the given information, we have;

Add
both sides, we have;

Take LCM of 8 and 10 is, 40
⇒
Simplify:

Therefore, the average weight of new born otter was, 
Answer: We have two solutions:
1000 - 998 = 2
1001 - 999 = 2
Step-by-step explanation:
So we have the problem:
****-*** = 2
where each star is a different digit, so in this case, we have a 4 digit number minus a 3 digit number, and the difference is 2.
we know that if we have a number like 99*, we can add a number between 1 and 9 and we will have a 4-digit as a result:
So we could write this as:
1000 - 998 = 2
now, if we add one to each number, the difference will be the same, and the number of digits in each number will remain equal:
1000 - 998 + 1 - 1 = 2
(1000 + 1) - (998 + 1) = 2
1001 - 999 = 2
now, there is a trivial case where we can find other solutions where the digits can be zero, like:
0004 - 0002 = 2
But this is trivial, so we can ignore this case.
Then we have two different solutions.
Answer:
Diego is 14 years old.
Sister is 19
Step-by-step explanation:
x = Diego's age
<u>x</u><u> </u><u>+</u><u> </u><u>2</u><u>4</u>
2x-9 = 2
First to get rid of the fraction we multiply each side by 2
2(2x-9) = 2((x+24)/2)
4x-18 = x+24
The we isolate x
4x-18 = x+24
<u>-x+18 -x+18</u>
<u>3x</u> = <u>42</u> Now we divide each side 3
3 3
x = 14
So Diego is 14
Now we can solve for his sister. We can use one of the two equations from earlier to do this.
Plug 14 in for x and then solve for his sister
2(14)-9
28-9
19
His sister is 19