Answer:
-3
4 - 7 = -3.
-3 + 7 = 4.
They are in a fact family.
The answer is -3.
Hope it helps!
3/4 + 1/2
multiply 1/2 denominator and numerator by 2 to match 3/4
= 3/4 + 2/4 = 5/4 (copy same denominator add numerator)
2/6 + 1/3
divide 2/6 denominator and numerator by 2 to match 1/3
= 1/3 + 1/3 = 2/3 (copy same denominator add numerator)
5/9 + 2/3
multiply 2/3 denominator and numerator by 3 to match 5/9
= 5/9 + 6/9 = 11/9 (copy same denominator add numerator)
6/9 -1/5
cross multiply 6x5 - 1x9 for numerator
for denominator multiply 9x5
=30/45 - 9/45= 21/45
divide num and den by 3
=7/15
5/8-1/3
cross multiply 5x3-1x8 for numerator
multiply 8x3 for denominator
= 15/24 -8/24 =7/24
Here is your answer
Money saved on each successive day is-
$3, &5, $7....
Clearly it forms an AP,
where
a1= 3
common difference, d= 2
n=20
So,
using formula
Tn= a1+(n-1)d
T20= 3+(20-1)2
= 3+ 19×2
= 3+ 38
=41
So, money saved on August 20= $41
Sum of money saved upto August 20 =
n/2 (a1+T20)
= 20/2 (3+41)
= 10× 44
= $440
HOPE IT IS USEFUL