Let Joy be x years old
<span>Joy's brother's age is 3 years older than twice joy's age.
</span>Joy's Brother = 2x + 3
<span>The sum of Joy's age and her brother's age is 24.
x + 2x + 3 = 24
3x + 3 = 24
3x = 24 - 3
3x = 21
x = 21 </span>÷ 3
x = 7
Joy:
x = 7
Brother:
2x + 3 = 2(7) + 3 = 17
Difference in their age = 17 - 7 = 10 years
They are 10 years apart.
<span>Lennie used
associative law of addition.
Associative law of addition doesn’t matter how you group the given numbers to
add.
a + (b + c) = (a + b) + c
=> 19 + (11 + 37) or ( 19 + 11) + 37
=> 19 + (48) or (30) + 37
=> 67 or 67</span>
where is the rest of the question?
is that it?
So if brother was 10, 5 years ago, then 10+5=15, bro is 15 now
in 15 years, he will be 15+15=30 years old
345 in Standard Form is 3.45 x 10^2
This is because when in standard form the decimal should move to the right 2 times.