Answer:
1640
Step-by-step explanation:
Even, positive integers
2+4+6+8+10+12+14+16+18+20+22+24+26+28+30+32+34+36+38+40+42+44+46+48+50+52+54+56+58+60+62+64+66+68+70+72+74+76+78+80 = 1640
Answer:
0.3
Step-by-step explanation:
x is the number to be added to 0.7 to have a sum of 1.
The top one is the answer
Answer:
x = 10
Step-by-step explanation:
Solve for x:
-8 (8 - x) = (4 (x + 10))/5
Multiply both sides by 5:
-8×5 (8 - x) = (5×4 (x + 10))/5
(5×4 (x + 10))/5 = 5/5×4 (x + 10) = 4 (x + 10):
-8×5 (8 - x) = 4 (x + 10)
5 (-8) = -40:
-40 (8 - x) = 4 (x + 10)
Expand out terms of the left hand side:
40 x - 320 = 4 (x + 10)
Expand out terms of the right hand side:
40 x - 320 = 4 x + 40
Subtract 4 x from both sides:
(40 x - 4 x) - 320 = (4 x - 4 x) + 40
40 x - 4 x = 36 x:
36 x - 320 = (4 x - 4 x) + 40
4 x - 4 x = 0:
36 x - 320 = 40
Add 320 to both sides:
36 x + (320 - 320) = 320 + 40
320 - 320 = 0:
36 x = 40 + 320
40 + 320 = 360:
36 x = 360
Divide both sides of 36 x = 360 by 36:
(36 x)/36 = 360/36
36/36 = 1:
x = 360/36
The gcd of 360 and 36 is 36, so 360/36 = (36×10)/(36×1) = 36/36×10 = 10:
Answer: x = 10
