To make this easy let covert everything using a LCD.
The LCD of 1/4 1/12 and 1/6 is 12. This becomes...
Tom ate 3/12 of the pizza.
Leftover pizza = 9/12.
Slices were 1/12.
X friends got pizza.
Remaining pizza is 2/12.
if each friend got 1 piece(1/12)....
9/12(Leftovers) - 2/12(remaining) = 7/12
So 7 friends got pizza.
Both of them together have 690 because you subtract 152 from 421 so...
421-152=269
Then add 269 to 421
421+269=690
D = # of dimes
n= # of nickles
d + n = 34 so d = 34 - n
.10d + .05n = 2.05
substitute d = 34 - n into .10d + .05n = 2.05
.10d + .05n = 2.05
.10( 34 - n) + .05n = 2.05
3.4 - .1n + .05n = 2.05
-.05n = -1.35
n = 27
d = 34 - n
d = 34 - 27
d = 7
answer
<span>she received 7 dimes and 27 nickels</span>
I WOULD DO THE EASIEST, A.