Answer:
Sol1 you can use "first(first+last)/2" is 138(138+1)/2 - 38(38+1)/2 = 8850
Sol2 or you can look this 39+40+41+....+100+(100+1)+(100+2)+....+(100+38) = 1+2+3+.....+99+100+100(38) = 5050+3800 =8850
I can’t help don’t have any question and photo
2/20 = 1/10 = 3/30 = 4/40
so 3 equivalent ratios can be 1/10 (or 1:10), 3/30 (or 3:30), 4/40 (or 4:40)
Is there a picture that I can see of the question
Q = p(r + s)
Use the distributive property
Q = pr + ps
Q = p x r + p x s
Q = p x p + r x s
Q = p^2 + rs
Subtract rs from both sides
Q - rs = p^2
Square root both sides
sqrt Q - rs = p
