The cost of an apple is twice that of a banana and the cost of a banana is 25% less than that of a guava. If the cost of each type of fruit increases by 10%, then the percentage increases in cost of 4 bananas, 2 apples and 3 guavas is?

To solve this problem, we first need to establish the initial cost of each fruit. Let's assume the cost of a guava is $1.

1. Since the cost of a banana is 25% less than that of a guava, the cost of a banana is $0.75.
2. The cost of an apple, which is twice that of a banana, is $1.50.

Next, we calculate the total initial cost of 4 bananas, 2 apples, and 3 guavas:

1. 4 bananas cost 4 * $0.75 =$3.00
2. 2 apples cost 2 * $1.50 =$3.00
3. 3 guavas cost 3 * $1.00 =$3.00

So, the total initial cost is $3.00 +$3.00 + $3.00 =$9.00

Now, let's calculate the new cost if the cost of each type of fruit increases by 10%:

1. The new cost of a banana is $0.75 * 1.10 =$0.825
2. The new cost of an apple is $1.50 * 1.10 =$1.65
3. The new cost of a guava is $1.00 * 1.10 =$1.10

The total new cost of 4 bananas, 2 apples, and 3 guavas is:

1. 4 bananas cost 4 * $0.825 =$3.30
2. 2 apples cost 2 * $1.65 =$3.30
3. 3 guavas cost 3 * $1.10 =$3.30

So, the total new cost is $3.30 +$3.30 + $3.30 =$9.90

Finally, to find the percentage increase in cost, we subtract the initial total cost from the new total cost, divide by the initial total cost, and multiply by 100:

Percentage increase = (($9.90 -$9.00) / $9.00) * 100 = 10%

So, the percentage increase in cost of 4 bananas, 2 apples, and 3 guavas is 10%.